If you use a filter on the backend and do something with the item the filters lose their values.
Test scenario:
- open VirtueMart -> Products
- Search for a product name
- publish/unpublish it
Also it would be great to use another filters, too. E.g. published status, parent or child, etc
Tested with Joomla 3.4.5 & VirtueMart 3.0.11