I'm not sure why - all the fields for the report should show up in the select expert, so even though you haven't seen say DestinationAccount of npauls, you should be able to add a target criteria of DestinationAccount (is) npauls. Exactly what hitnrunxx said - run the report once for whatever critieria, then add your own.
Unless you mean you want to specify the criteria first, more like an nDepth search?