diff --git a/mopidy/mpd/protocol/music_db.py b/mopidy/mpd/protocol/music_db.py
index 769cc80b..9497cde7 100644
--- a/mopidy/mpd/protocol/music_db.py
+++ b/mopidy/mpd/protocol/music_db.py
@@ -42,7 +42,7 @@ def _query_from_mpd_search_parameters(parameters, mapping):
         if not parameters:
             raise ValueError
         value = parameters.pop(0)
-        if value:
+        if value.strip():
             query.setdefault(field, []).append(value)
     return query