Update README.md

extensions/elasticsearch/README.md

@@ -144,11 +144,11 @@ $customer->save();
 
 $customer = Customer::get(1); // get a record by pk
 $customers = Customer::mget([1,2,3]); // get multiple records by pk
-$customer = Customer::find()->where(['name' => 'test'])->one(); // find by query
+$customer = Customer::find()->where(['name' => 'test'])->one(); // find by query, note that you need to configure mapping for this field in order to find records properly
 $customers = Customer::find()->active()->all(); // find all by query (using the `active` scope)
 
-// http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/query-dsl-field-query.html
-$result = Article::find()->query(["field" => ["title" => "yii"]])->all(); // articles whose title contains "yii"
+// http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/query-dsl-match-query.html
+$result = Article::find()->query(["match" => ["title" => "yii"]])->all(); // articles whose title contains "yii"
 
 // http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/query-dsl-flt-query.html
 $query = Article::find()->query([