Depending on the quantity of ‘sometimes’, would a filter expression help out in those cases?

When switching to text view, it is clear that the condition is OR:

Another benefit in my view is that those texts can be saved, edited and shared externally, so that complex queries can be made without the need for back end SQL-access.

This idea is somewhat related, perhaps you'll find this one interesting too.

It would still be nice to have the possibility of a comma separated multi value search inside a combi filter or a filter form. :)