diff --git a/backend/crates/gateway-store/src/postgres/client_keys.rs b/backend/crates/gateway-store/src/postgres/client_keys.rs
index 252c254f9..2cd367f41 100644
--- a/backend/crates/gateway-store/src/postgres/client_keys.rs
+++ b/backend/crates/gateway-store/src/postgres/client_keys.rs
@@ -1484,12 +1484,12 @@ async fn count_client_api_keys(pool: &PgPool, search: Option<&str>) -> StoreResu
 
 fn push_client_key_search(statement: &mut QueryBuilder<Postgres>, search: Option<&str>) {
     if let Some(search) = search {
-        let prefix = crate::postgres::literal_prefix_pattern(search);
+        let pattern = crate::postgres::literal_contains_pattern(&search.to_lowercase());
         statement.push(" and (lower(name) like ");
-        statement.push_bind(prefix.clone());
+        statement.push_bind(pattern.clone());
         statement.push(" escape '\\'");
         statement.push(" or lower(coalesce(label, '')) like ");
-        statement.push_bind(prefix);
+        statement.push_bind(pattern);
         statement.push(" escape '\\'");
         statement.push(")");
     }
diff --git a/backend/crates/gateway-store/src/postgres/mod.rs b/backend/crates/gateway-store/src/postgres/mod.rs
index 86481846b..e6d05bc3b 100644
--- a/backend/crates/gateway-store/src/postgres/mod.rs
+++ b/backend/crates/gateway-store/src/postgres/mod.rs
@@ -43,7 +43,7 @@ pub use ops_events::*;
 pub use plugins::PgPluginStore;
 pub use provider_accounts::*;
 pub use proxies::PgProxyRepository;
-use query_pattern::literal_prefix_pattern;
+use query_pattern::literal_contains_pattern;
 pub use retention::*;
 pub use runtime_settings::*;
 pub use snapshot::*;
diff --git a/backend/crates/gateway-store/src/postgres/observability/mod.rs b/backend/crates/gateway-store/src/postgres/observability/mod.rs
index 6d77abba2..26ed34b24 100644
--- a/backend/crates/gateway-store/src/postgres/observability/mod.rs
+++ b/backend/crates/gateway-store/src/postgres/observability/mod.rs
@@ -19,7 +19,7 @@ use crate::{
 };
 
 use super::{
-    completed_usage_fact_predicate, push_completed_usage_fact_filter,
+    completed_usage_fact_predicate, literal_contains_pattern, push_completed_usage_fact_filter,
     push_unrecovered_request_filter,
 };
 
diff --git a/backend/crates/gateway-store/src/postgres/observability/queries/ops.rs b/backend/crates/gateway-store/src/postgres/observability/queries/ops.rs
index 0ee803f5a..19a1c4655 100644
--- a/backend/crates/gateway-store/src/postgres/observability/queries/ops.rs
+++ b/backend/crates/gateway-store/src/postgres/observability/queries/ops.rs
@@ -285,7 +285,7 @@ fn push_request_error_predicates(
         statement.push_bind(i32::from(status));
     }
     if let Some(search) = &filter.search {
-        push_prefix_search(
+        push_contains_search(
             statement,
             &[
                 "mr.id",
@@ -331,7 +331,7 @@ fn push_ops_event_predicates(
         statement.push_bind(i32::from(status));
     }
     if let Some(search) = &filter.search {
-        push_prefix_search(
+        push_contains_search(
             statement,
             &[
                 "oe.id",
@@ -375,8 +375,8 @@ fn push_response_id_filter(
     }
 }
 
-fn push_prefix_search(statement: &mut QueryBuilder<Postgres>, columns: &[&str], value: &str) {
-    let pattern = literal_prefix_pattern(value);
+fn push_contains_search(statement: &mut QueryBuilder<Postgres>, columns: &[&str], value: &str) {
+    let pattern = literal_contains_pattern(value);
     statement.push(" and (");
     for (index, column) in columns.iter().enumerate() {
         if index > 0 {
diff --git a/backend/crates/gateway-store/src/postgres/observability/queries/usage.rs b/backend/crates/gateway-store/src/postgres/observability/queries/usage.rs
index 47c96ea5c..58c97406f 100644
--- a/backend/crates/gateway-store/src/postgres/observability/queries/usage.rs
+++ b/backend/crates/gateway-store/src/postgres/observability/queries/usage.rs
@@ -100,7 +100,7 @@ pub(crate) fn push_usage_filter(
         query.push_bind(value.clone());
     }
     if let Some(value) = &filter.search {
-        let pattern = literal_prefix_pattern(value);
+        let pattern = literal_contains_pattern(value);
         query.push(format!(" and ({alias}.requested_model_id like "));
         query.push_bind(pattern.clone());
         for column in [
@@ -123,20 +123,6 @@ pub(crate) fn push_usage_filter(
     }
 }
 
-fn literal_contains_pattern(value: &str) -> String {
-    format!("%{}", literal_prefix_pattern(value))
-}
-
-pub(crate) fn literal_prefix_pattern(value: &str) -> String {
-    format!(
-        "{}%",
-        value
-            .replace('\\', "\\\\")
-            .replace('%', "\\%")
-            .replace('_', "\\_")
-    )
-}
-
 pub(crate) const USAGE_LIST_RECORD_SELECT: &str =
     "select mr.id, mr.outcome, mr.provider_error_code as error_code, mr.error_message, mr.client_status_code, mr.client_api_key_name_snapshot as client_api_key_name, mr.endpoint, mr.client_transport, mr.requested_model_id,
             mr.provider_kind, mr.provider_account_ref,
diff --git a/backend/crates/gateway-store/src/postgres/provider_accounts/admin_queries.rs b/backend/crates/gateway-store/src/postgres/provider_accounts/admin_queries.rs
index 37b0f1994..78593b004 100644
--- a/backend/crates/gateway-store/src/postgres/provider_accounts/admin_queries.rs
+++ b/backend/crates/gateway-store/src/postgres/provider_accounts/admin_queries.rs
@@ -23,10 +23,10 @@ pub(crate) async fn load_admin_account_page(
         .provider_kind
         .as_ref()
         .map(|provider| provider.as_str().to_owned());
-    let search_prefix = query
+    let search_pattern = query
         .search
         .as_deref()
-        .map(crate::postgres::literal_prefix_pattern);
+        .map(|search| crate::postgres::literal_contains_pattern(&search.to_lowercase()));
     let status = query.status.map(|status| status.as_str().to_owned());
     let (group_mode, group_id) = match query.group_filter.as_ref() {
         None => (0_i16, None),
@@ -79,11 +79,8 @@ pub(crate) async fn load_admin_account_page(
              join provider_accounts a on a.id = status.id
             where ($3::text is null or a.provider_kind = $3)
               and ($4::text is null or
-                   lower(a.id) like $4 escape '\\' or
                    lower(a.name) like $4 escape '\\' or
-                   lower(coalesce(a.email, '')) like $4 escape '\\' or
-                   lower(coalesce(a.upstream_account_id, '')) like $4 escape '\\' or
-                   lower(coalesce(a.upstream_user_id, '')) like $4 escape '\\')
+                   lower(coalesce(a.email, '')) like $4 escape '\\')
               and ($5::text is null or status.admin_status = $5)
               and ($6::smallint = 0 or
                    ($6 = 1 and exists (
@@ -157,7 +154,7 @@ pub(crate) async fn load_admin_account_page(
                     .bind(active_rate_limited_ids)
                     .bind(now)
                     .bind(provider_kind)
-                    .bind(search_prefix)
+                    .bind(search_pattern)
                     .bind(status)
                     .bind(group_mode)
                     .bind(group_id)
diff --git a/backend/crates/gateway-store/src/postgres/query_pattern.rs b/backend/crates/gateway-store/src/postgres/query_pattern.rs
index e44a664be..7c17bd53f 100644
--- a/backend/crates/gateway-store/src/postgres/query_pattern.rs
+++ b/backend/crates/gateway-store/src/postgres/query_pattern.rs
@@ -1,8 +1,9 @@
-//! 管理实体搜索共用的 SQL 字面前缀转义
+//! PostgreSQL 包含搜索共用的 SQL 字面量转义，大小写规则由调用方决定
 
-pub(super) fn literal_prefix_pattern(value: &str) -> String {
-    let mut escaped = String::with_capacity(value.len().saturating_add(1));
-    for character in value.to_lowercase().chars() {
+pub(super) fn literal_contains_pattern(value: &str) -> String {
+    let mut escaped = String::with_capacity(value.len().saturating_add(2));
+    escaped.push('%');
+    for character in value.chars() {
         if matches!(character, '\\' | '%' | '_') {
             escaped.push('\\');
         }
diff --git a/backend/crates/gateway-store/tests/postgres/analytics.rs b/backend/crates/gateway-store/tests/postgres/analytics.rs
index 32ccc03cd..dc9fea1ad 100644
--- a/backend/crates/gateway-store/tests/postgres/analytics.rs
+++ b/backend/crates/gateway-store/tests/postgres/analytics.rs
@@ -455,8 +455,8 @@ async fn insights_share_bucket_states_without_merging_exact_percentiles() {
 }
 
 #[tokio::test]
-async fn prefix_search_ignores_request_ids_and_matches_snapshot_names() {
-    let Some(database) = TestDatabase::create("analytics_search_prefix").await else {
+async fn contains_search_ignores_request_ids_and_matches_snapshot_names() {
+    let Some(database) = TestDatabase::create("analytics_search_contains").await else {
         return;
     };
     let start = Utc::now() - TimeDelta::hours(1);
@@ -471,7 +471,7 @@ async fn prefix_search_ignores_request_ids_and_matches_snapshot_names() {
             ObservabilityRange::new(start - TimeDelta::seconds(1), start + TimeDelta::seconds(1))
                 .unwrap(),
             UsageRecordFilter {
-                search: Some("literal_".to_owned()),
+                search: Some("eral_".to_owned()),
                 ..Default::default()
             },
         )
diff --git a/backend/crates/gateway-store/tests/postgres/client_keys.rs b/backend/crates/gateway-store/tests/postgres/client_keys.rs
index 0793fe393..399d576ec 100644
--- a/backend/crates/gateway-store/tests/postgres/client_keys.rs
+++ b/backend/crates/gateway-store/tests/postgres/client_keys.rs
@@ -256,7 +256,7 @@ async fn client_key_search_matches_names_and_labels_but_never_credential_values(
     let generated = format!("sk_{}", "K".repeat(43));
     for (id, name, key) in [
         ("key_generated", "Production", generated.as_str()),
-        ("key_custom", "生产_%专用", "legacy-token+/123"),
+        ("key_custom", r"生产_%专用\测试", "legacy-token+/123"),
     ] {
         sqlx::query(
             "insert into client_api_keys (id, name, label, key, created_at, updated_at)
@@ -272,9 +272,17 @@ async fn client_key_search_matches_names_and_labels_but_never_credential_values(
     let repository = PgClientApiKeyRepository::new(database.pool.clone());
     for (search, expected) in [
         ("PROD", 1),
+        ("DUCt", 1),
+        ("tion", 1),
         ("生产_%", 1),
+        ("_%专", 1),
+        ("%", 1),
+        ("_", 1),
+        (r"\", 1),
         ("生产X", 0),
         ("backend", 2),
+        ("END LAB", 2),
+        ("label", 2),
         (generated.as_str(), 0),
         (&generated[..10], 0),
         ("legacy-token+/123", 0),
diff --git a/backend/crates/gateway-store/tests/postgres/observability/mod.rs b/backend/crates/gateway-store/tests/postgres/observability/mod.rs
index 43ab3fe36..da4aa5dec 100644
--- a/backend/crates/gateway-store/tests/postgres/observability/mod.rs
+++ b/backend/crates/gateway-store/tests/postgres/observability/mod.rs
@@ -498,37 +498,6 @@ async fn usage_list_and_diagnostics_preserve_account_snapshots_by_id() {
     database.close().await;
 }
 
-#[tokio::test]
-async fn usage_search_should_match_literal_prefix_instead_of_substring() {
-    let Some(database) = TestDatabase::create("usage_literal_prefix_search").await else {
-        return;
-    };
-    let now = Utc::now();
-    seed_observability_facts(&database.pool, now)
-        .await
-        .expect("seed observability facts");
-    let range = ObservabilityRange::new(now - TimeDelta::hours(1), now + TimeDelta::hours(1))
-        .expect("observability range");
-
-    super::drain_analytics(&database.pool).await;
-    let page = observability_repository(&database.pool)
-        .list_usage_records(UsageRecordQuery {
-            status: Default::default(),
-            range,
-            filter: UsageRecordFilter {
-                search: Some("rimary".to_owned()),
-                ..UsageRecordFilter::default()
-            },
-            current_page: 1,
-            page_size: ObservabilityPageSize::new(10).expect("page size"),
-        })
-        .await
-        .expect("usage substring search");
-
-    assert_eq!(page.total, 0);
-    database.close().await;
-}
-
 #[tokio::test]
 async fn usage_search_should_ignore_request_ids_and_preserve_exact_filters() {
     let Some(database) = TestDatabase::create("usage_search_without_request_ids").await else {
@@ -576,8 +545,8 @@ async fn usage_search_should_ignore_request_ids_and_preserve_exact_filters() {
 }
 
 #[tokio::test]
-async fn usage_search_should_match_account_email_and_name_prefixes() {
-    let Some(database) = TestDatabase::create("usage_account_prefix").await else {
+async fn usage_search_should_match_account_email_and_name_substrings() {
+    let Some(database) = TestDatabase::create("usage_account_contains").await else {
         return;
     };
     let now = Utc::now();
@@ -587,10 +556,18 @@ async fn usage_search_should_match_account_email_and_name_prefixes() {
     let range = ObservabilityRange::new(now - TimeDelta::hours(1), now + TimeDelta::hours(1))
         .expect("observability range");
 
-    for search in ["account@example.invalid", "account@", "primary", "pri"] {
+    for search in [
+        "account@example.invalid",
+        "account@",
+        "primary",
+        "pri",
+        "count@example.invalid",
+        "example.invalid",
+        "rimary",
+    ] {
         assert_usage_search_ids(&database.pool, range, search, &["req_observe_success"]).await;
     }
-    for search in ["count@example.invalid", "rimary", "missing@example.invalid"] {
+    for search in ["missing@example.invalid", "EXAMPLE.INVALID", "PRIMARY"] {
         assert_usage_search_ids(&database.pool, range, search, &[]).await;
     }
 
@@ -679,9 +656,13 @@ async fn usage_search_should_treat_account_snapshot_wildcards_as_literals() {
         "account_team%tag@example.invalid",
         "account_",
         "account_team%",
+        "team%tag",
+        "_team%",
         r"primary\",
         r"primary\ops_",
         r"primary\ops_100%",
+        r"\ops_",
+        "100%",
     ] {
         assert_usage_search_ids(&database.pool, range, search, &["req_observe_success"]).await;
     }
@@ -761,6 +742,9 @@ async fn usage_and_error_search_match_key_names_instead_of_credentials() {
         for (search, expected) in [
             ("production", 1),
             ("PRODUCTION_%", 1),
+            ("DUCTION", 1),
+            ("_%专", 1),
+            ("专用", 1),
             ("ProductionX", 0),
             (key, 0),
             (&key[..10], 0),
@@ -863,8 +847,8 @@ async fn usage_and_error_search_match_key_names_instead_of_credentials() {
 }
 
 #[tokio::test]
-async fn ops_search_should_treat_sql_wildcards_as_literals() {
-    let Some(database) = TestDatabase::create("ops_literal_wildcard_search").await else {
+async fn ops_search_should_match_literal_substrings_from_both_sources() {
+    let Some(database) = TestDatabase::create("ops_literal_contains_search").await else {
         return;
     };
     let now = Utc::now();
@@ -875,20 +859,38 @@ async fn ops_search_should_treat_sql_wildcards_as_literals() {
         .expect("observability range");
 
     super::drain_analytics(&database.pool).await;
-    let page = observability_repository(&database.pool)
-        .list_ops_errors(OpsErrorQuery {
-            range,
-            filter: OpsErrorFilter {
-                search: Some("req%".to_owned()),
-                ..OpsErrorFilter::default()
-            },
-            current_page: 1,
-            page_size: ObservabilityPageSize::new(10).expect("page size"),
-        })
-        .await
-        .expect("ops literal wildcard search");
-
-    assert_eq!(page.total, 0);
+    let repository = observability_repository(&database.pool);
+    for (search, expected) in [
+        ("observe_failed", 2),
+        ("_limit", 2),
+        ("observe_retry", 1),
+        ("OBSERVE", 0),
+        ("req%", 0),
+        ("rate%limit", 0),
+        ("rate__limit", 0),
+        (r"\", 0),
+    ] {
+        for current_page in 1..=3 {
+            let page = repository
+                .list_ops_errors(OpsErrorQuery {
+                    range,
+                    filter: OpsErrorFilter {
+                        search: Some(search.to_owned()),
+                        ..OpsErrorFilter::default()
+                    },
+                    current_page,
+                    page_size: ObservabilityPageSize::new(1).expect("page size"),
+                })
+                .await
+                .expect("ops literal substring search");
+            assert_eq!(page.total, expected, "search: {search}");
+            assert_eq!(
+                page.items.len(),
+                usize::from(u64::from(current_page) <= expected),
+                "search: {search}, page: {current_page}"
+            );
+        }
+    }
     database.close().await;
 }
 
diff --git a/backend/crates/gateway-store/tests/postgres/provider_accounts/admin_adapter.rs b/backend/crates/gateway-store/tests/postgres/provider_accounts/admin_adapter.rs
index 46e763140..b8ee94cde 100644
--- a/backend/crates/gateway-store/tests/postgres/provider_accounts/admin_adapter.rs
+++ b/backend/crates/gateway-store/tests/postgres/provider_accounts/admin_adapter.rs
@@ -91,6 +91,60 @@ async fn account_capacity_should_resolve_limits_for_list_and_detail() {
     database.close().await;
 }
 
+#[tokio::test]
+async fn account_search_matches_only_name_and_email_literal_substrings() {
+    let Some(database) = TestDatabase::create("account_contains_search").await else {
+        return;
+    };
+    let repository = PgProviderAccountRepository::new(database.pool.clone());
+    let mut record = account("acct_searchable", "upstream-user-needle");
+    record.name = r"Team\Ops_100%".to_owned();
+    record.email = Some("maker@example.invalid".to_owned());
+    record.upstream_account_id = Some("upstream-account-marker".to_owned());
+    repository.insert_provider_account(record).await.unwrap();
+    let mut other = account("acct_other", "user-other");
+    other.email = None;
+    repository.insert_provider_account(other).await.unwrap();
+    let store = admin_account_store(&database.pool);
+    for (search, expected) in [
+        ("ma", 1),
+        ("ak", 1),
+        ("EXAMPLE", 1),
+        ("invalid", 1),
+        (r"\OPS_", 1),
+        ("_100%", 1),
+        ("%", 1),
+        (r"\", 1),
+        ("searchable", 0),
+        ("user-needle", 0),
+        ("account-marker", 0),
+        ("Ops_100_", 0),
+        ("missing", 0),
+    ] {
+        let page = store
+            .list_accounts(
+                AccountListQuery {
+                    page: 1,
+                    page_size: PageSize::new(10).unwrap(),
+                    provider_kind: None,
+                    group_filter: None,
+                    search: Some(search.to_owned()),
+                    status: None,
+                    sort: None,
+                },
+                Default::default(),
+            )
+            .await
+            .unwrap();
+        assert_eq!(page.total, expected, "search: {search}");
+        assert_eq!(page.items.len() as u64, expected, "search: {search}");
+        if expected == 1 {
+            assert_eq!(page.items[0].account.id, "acct_searchable");
+        }
+    }
+    database.close().await;
+}
+
 #[tokio::test]
 async fn provider_filter_applies_before_pagination_even_on_an_empty_page() {
     let Some(database) = TestDatabase::create("account_provider_filters").await else {
diff --git a/backend/crates/gateway-store/tests/postgres/provider_accounts/mod.rs b/backend/crates/gateway-store/tests/postgres/provider_accounts/mod.rs
index 2c5b29690..762a9e226 100644
--- a/backend/crates/gateway-store/tests/postgres/provider_accounts/mod.rs
+++ b/backend/crates/gateway-store/tests/postgres/provider_accounts/mod.rs
@@ -827,7 +827,7 @@ async fn terminal_admin_list_filters_and_sorts_before_pagination_with_retained_u
                 page_size: PageSize::new(10).expect("page size"),
                 provider_kind: Some(ProviderKind::new("openai").expect("Provider kind")),
                 group_filter: None,
-                search: Some("ALPHA@EXAMPLE".to_owned()),
+                search: Some("PHA@EXAM".to_owned()),
                 status: Some(AccountStatus::Normal),
                 sort: None,
             },
@@ -866,11 +866,11 @@ async fn terminal_admin_list_filters_and_sorts_before_pagination_with_retained_u
     assert_eq!(rate_limited.summary.rate_limited, 1);
     assert_eq!(rate_limited.summary.normal, 0);
 
-    let no_contains_compatibility = store
+    let email_domain_page = store
         .list_accounts(
             AccountListQuery {
-                page: 1,
-                page_size: PageSize::new(10).expect("page size"),
+                page: 2,
+                page_size: PageSize::new(2).expect("page size"),
                 provider_kind: None,
                 group_filter: None,
                 search: Some("example.invalid".to_owned()),
@@ -880,8 +880,10 @@ async fn terminal_admin_list_filters_and_sorts_before_pagination_with_retained_u
             Default::default(),
         )
         .await
-        .expect("use structured account prefix search");
-    assert_eq!(no_contains_compatibility.total, 0);
+        .expect("search accounts by email domain before pagination");
+    assert_eq!(email_domain_page.total, 6);
+    assert_eq!(email_domain_page.items.len(), 2);
+    assert_eq!(email_domain_page.summary, usage_page.summary);
 
     let error_accounts = store
         .list_accounts(
diff --git a/docs/api.md b/docs/api.md
index 7b877068f..44970b8d3 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -779,6 +779,8 @@ config 返回 `{ name, plaintextKey }`，仅读取服务端会话绑定的当前
 - `sortBy`: `email`、`status`、`planType`、`usage`、`lastUsedAt`、`expiresAt`
 - `sortDirection`: `asc`、`desc`
 
+账号列表的 `search` 仅按字面量包含匹配名称和邮箱，不区分大小写；`%`、`_` 和 `\` 按普通字符处理
+
 账号视图的 `capacity` 返回查询时的普通并发容量：`usedSlots` 不含独立审批池和排队请求，
 读取运行态失败时为 `null`；`totalSlots` 是应用账号独立配置或全局默认值后的上限，`null` 表示不限。
 该上限不代表上游实际允许的并发数
@@ -1428,7 +1430,7 @@ HTTP 返回 `403` 和 `image_generation_disabled`，WebSocket 每个 `response.c
 创建时省略或 `null` 表示无覆盖；更新时省略保留、`null` 清除。与通用字段同时提交时必须一致，否则拒绝整个请求；
 响应中的兼容字段从同一映射派生，不是第二份配置
 
-密钥列表的 `search` 仅匹配名称和标签，不匹配密钥值或可见前缀；搜索不区分大小写，使用字面量前缀匹配。
+密钥列表的 `search` 仅匹配名称和标签，不匹配密钥值或可见前缀；搜索不区分大小写，使用字面量包含匹配，`%`、`_` 和 `\` 按普通字符处理。
 创建和更新时去除名称首尾空白，并按忽略大小写、首尾空格的名称查重，重复返回 `409`。
 更新排除当前记录，并发写入同样执行查重；失败不会留下审计或配置版本变更。
 历史重名数据不自动改名，已有凭据继续有效；再次保存时需使用未被其他密钥占用的名称
@@ -2111,7 +2113,7 @@ Dashboard 返回原始 `asOf` 及 `asOfDisplay`，作为当前数据的查询锚
 请求明细的 `clientApiKeyName`、`accountName` 按字面量包含匹配请求保存的历史名称快照，区分大小写，
 不解析为 ID，也不依赖当前配置是否存在。`model` 按字面量包含匹配请求模型或上游模型，`%`、`_` 和 `\` 按普通字符处理
 
-运维错误列表的 `search` 使用字面量前缀匹配，不支持密钥值或可见前缀搜索。
+运维错误列表的 `search` 使用字面量包含匹配，`%`、`_` 和 `\` 按普通字符处理，不支持密钥值或可见前缀搜索。
 请求详情通过 `/api/admin/usage/records/detail?id=...` 查询
 
 ### 记录范围与统计口径