diff --git a/discovery/model/schema.py b/discovery/model/schema.py
index 74d3ae12..e7c82528 100644
--- a/discovery/model/schema.py
+++ b/discovery/model/schema.py
@@ -9,8 +9,16 @@
 import functools
 from datetime import datetime
 
-from elasticsearch_dsl import Boolean, Date, InnerDoc, Integer, Keyword, Object, Text
-from elasticsearch_dsl import Index as ESIndex
+from elasticsearch_dsl import (
+    Boolean,
+    Date,
+    Index as ESIndex,
+    InnerDoc,
+    Integer,
+    Keyword,
+    Object,
+    Text,
+)
 from elasticsearch_dsl.exceptions import ValidationException
 
 from .common import DiscoveryDoc, DiscoveryMeta, DiscoveryUserDoc
@@ -23,7 +31,6 @@ def mergeDict(d1, d2):
 
 
 class SchemaMeta(DiscoveryMeta):
-
     url = Keyword(required=True)
     # timestamp = Date()  # when this document is updated
     last_updated = Date()
@@ -32,7 +39,6 @@ class SchemaMeta(DiscoveryMeta):
 
 
 class SchemaStatusMeta(InnerDoc):
-
     refresh_status = Integer()
     refresh_ts = Date()
     refresh_msg = Text(index=False)
@@ -74,7 +80,6 @@ class Index:
             "number_of_replicas": 0,
         }
 
-
     def update_index_meta(self, meta):
         allowed_keys = {"_meta"}
         if isinstance(meta, dict) and len(set(meta) - allowed_keys) == 0:
@@ -171,7 +176,11 @@ class SchemaClass(DiscoveryDoc):
     uri = Text(fields={"raw": Keyword()})
     parent_classes = Text(multi=True, analyzer="simple")  # immediate ones only
     properties = Object(SchemaClassProp)  # immediate ones only
-    validation = Object(enabled=False)
+    validation = Object(
+        dynamic=False,  # only index fields listed
+        # indexing fields, validation.$schema(.raw) & validation.type, to allow filter/query on
+        properties={"$schema": Text(fields={"raw": Keyword()}), "type": Keyword()},
+    )  # nested properties for filter
     ref = Boolean()  # not defined in this schema
 
     class Index:
@@ -186,6 +195,5 @@ class Index:
         }
 
     def save(self, **kwargs):
-
         self.meta.id = f"{self.namespace}::{self.prefix}:{self.label}"
         return super().save(**kwargs)
diff --git a/discovery/pipeline.py b/discovery/pipeline.py
index 8f21b8dc..9ad96e30 100644
--- a/discovery/pipeline.py
+++ b/discovery/pipeline.py
@@ -13,35 +13,44 @@
 
 class DiscoveryQueryBuilder(ESQueryBuilder):
     def default_string_query(self, q, options):
-
         search = Search()
-        search = search.update_from_dict(
-            {
-                "query": {
-                    "function_score": {
-                        "query": {
-                            "dis_max": {
-                                "queries": [
-                                    {"term": {"_id": {"value": q, "boost": 15.0}}},
-                                    {"term": {"label.raw": {"value": q, "boost": 10.0}}},
-                                    {"term": {"_meta.username": {"value": q}}},  # for dataset
-                                    {"term": {"name": {"value": q}}},
-                                    {"match": {"parent_classes": {"query": q}}},
-                                    {"prefix": {"label": {"value": q}}},
-                                    {"query_string": {"query": q}},
-                                ]
-                            }
-                        },
-                        "functions": [
-                            {"filter": {"term": {"namespace": "schema"}}, "weight": 0.5},
-                            {"filter": {"term": {"prefix.raw": "schema"}}, "weight": 0.5},
-                            {
-                                "filter": {"match": {"parent_classes": "bts:BiologicalEntity"}},
-                                "weight": 1.5,
+        q = q.strip()
+
+        # Check for other elasticsearch query string syntax
+        if ":" in q or " AND " in q or " OR " in q:
+            search = search.query("query_string", query=q)
+        else:
+            # Update the search with the constructed query
+            search = search.update_from_dict(
+                {
+                    "query": {
+                        "function_score": {
+                            "query": {
+                                "dis_max": {
+                                    "queries": [
+                                        {"term": {"_id": {"value": q, "boost": 15.0}}},
+                                        {"term": {"label.raw": {"value": q, "boost": 10.0}}},
+                                        {"term": {"_meta.username": {"value": q}}},
+                                        {"term": {"name": {"value": q}}},
+                                        {"match": {"parent_classes": {"query": q}}},
+                                        {"prefix": {"label": {"value": q}}},
+                                        {"query_string": {"query": q}},
+                                    ]
+                                }
                             },
-                        ],
-                    }
+                            "functions": [
+                                {"filter": {"term": {"namespace": "schema"}}, "weight": 0.5},
+                                {"filter": {"term": {"prefix.raw": "schema"}}, "weight": 0.5},
+                                {
+                                    "filter": {
+                                        "match": {"parent_classes": "bts:BiologicalEntity"}
+                                    },
+                                    "weight": 1.5,
+                                },
+                            ],
+                        }
+                    },
                 }
-            }
-        )
+            )
+
         return search