Profile completeness from CB Progress Fields isn't stored in the database so you won't be able to filter on it. Easiest way to do that though is to add multiple OR filters to your userlist to check if any of your required fields is empty. You will have to use an Advanced filter, which lets you directly add to the query WHERE statement. Example as follows.
Filters
Advanced
Code:
`cb_field1` = ''
OR `cb_field2` = ''
This should check if cb_field1 or cb_field2 is an empty string and display all users with fields matching those 2 if either are empty. Your query would of course be dependent on what type of field you're checking against.