diff --git a/Products/zms/rest_api.py b/Products/zms/rest_api.py
index e1fef9579..f4e1a6cf5 100644
--- a/Products/zms/rest_api.py
+++ b/Products/zms/rest_api.py
@@ -90,8 +90,8 @@ def __call__(self, REQUEST=None, **kw):
             if context.meta_type == 'ZMSIndex':
                 data = []
                 catalog = context.get_catalog()
-                q = {k:v for k,v in REQUEST.form.items()}
-                l = catalog(REQUEST.form)
+                q = {k:v for k,v in REQUEST.form.items() if v is not ''}
+                l = catalog(q)
                 data = [{item_name:r[item_name] for item_name in catalog.schema()} for r in l]
             elif context.meta_type == 'ZMSMetamodelProvider':
                 data = {}