diff --git a/src/caosdb/common/models.py b/src/caosdb/common/models.py
index 5ced1e382909df7bad21464f98c08e64ff2321ac..8de67513e3adf896fbddc0914c8c4c298e71da65 100644
--- a/src/caosdb/common/models.py
+++ b/src/caosdb/common/models.py
@@ -49,7 +49,7 @@ from caosdb.connection.encode import MultipartParam, multipart_encode
 from caosdb.exceptions import (AmbiguityException,
                                AuthorizationException,
                                CaosDBException, ConnectionException,
-                               ConsistencyError, ContainerError,
+                               ConsistencyError,
                                EntityDoesNotExistError, EntityError,
                                EntityHasNoDatatypeError,
                                TransactionError, UniqueNamesError,
@@ -3480,9 +3480,11 @@ class Query():
 
         if unique:
             if len(cresp) > 1 and raise_exception_on_error:
-                raise AmbiguityException("This query wasn't unique")
+                raise AmbiguityException("Query '{}' wasn't unique.".format(q))
             elif len(cresp) == 0 and raise_exception_on_error:
-                raise EntityDoesNotExistError("No such entity found.")
+                ee = EntityDoesNotExistError(
+                    "Query '{}' found no results.".format(q))
+                raise TransactionError(ee)
             elif len(cresp) == 1:
                 r = cresp[0]
                 r.messages.extend(cresp.messages)