WORKAROUND
Please follow the steps below for the current workaround:
1. In the Filter enter your properties you want to filter, then go to the SQL tab.
2. Check "Enable Custom SQL" and add the “i.” correlation name to TABSCHEMA. So it will look like Lower (i.TABSCHEMA) LIKE ....
3. Hit OK and now it should work.
STATUS
Waiting for fix in a future release of (Toad for DB2 LUW)