About operations between newgroups

[JackieChun]

Is there a way to do an AND operation between 2 or more newsgroups with headers already downloaded ? I know that when I put those newsgroups in a folder its like an OR operation between them. I also know that I can do a search with those groups ANDed (using boolean wildmats) or even I can filter the results of the search by newsgroups. Is there a way to create a filter with n groups ANDed or using (in general) boolean wildmats ? Or is there a way to create a folder with the AND of the newsgroups it contents ?

[JackieChun]

I was testing search service filters and it only filters over 1 newsgroup name, not between several newsgroups. Also the same in search results. That's not what I was looking for. If I have a.b.c and a.b.d newsgroups and create a filter with c&d I would like to get headers that are in both groups. Is that possible using filters or in any other way ?