explanation kind of working in an ugly way.

src/query/query_parser.rs

@@ -8,6 +8,9 @@ use schema::Schema;
 use schema::{Term, Field};
 use analyzer::SimpleTokenizer;
 use analyzer::StreamingIterator;
+use DocAddress;
+use Score;
+use query::Explanation;
 
 #[derive(Debug)]
 pub enum ParsingError {
@@ -43,8 +46,16 @@ impl Query for StandardQuery {
             }
         }
     }
-}
 
+    fn explain(
+        &self,
+        searcher: &Searcher,
+        doc_address: &DocAddress) -> Result<Option<(Score, Explanation)>, io::Error> {
+        match self {
+            &StandardQuery::MultiTerm(ref q) => q.explain(searcher, doc_address)
+        }
+    }
+}
 
 fn compute_terms(field: Field, text: &str) -> Vec<Term> {
     let tokenizer = SimpleTokenizer::new();