diff --git a/core/apps/wherehouse/views/inventory.py b/core/apps/wherehouse/views/inventory.py
index 51dba94..3c4bf62 100644
--- a/core/apps/wherehouse/views/inventory.py
+++ b/core/apps/wherehouse/views/inventory.py
@@ -34,10 +34,10 @@ class InventoryListApiView(generics.GenericAPIView):
             inventories = inventories.filter(project_folder__in=project_folder_ids)
         if project_ids:
             inventories = inventories.filter(project__in=project_ids)
-        if product_exists == 'true':
-            inventories = inventories.exclude(quantity=0)
-        elif product_exists == 'false':
-            inventories = inventories.filter(quantity=0) 
+        if product_exists.lower() == 'true':
+            inventories = inventories.exclude(quantity__lte=0)
+        elif product_exists.lower() == 'false':
+            inventories = inventories.filter(quantity__lte=0) 
         if start_date and end_date:
             inventories = inventories.filter(created_at__range=(start_date, end_date))
         page = self.paginate_queryset(inventories)