It wouldn't necessarily search a particular folder, but it would search only folders that match the first filter. That would be quite helpful, I think, because it would allow you to more reasonably limit your searches. But setting aside the folder example, the more general suggestion is to have the ability to use multiple search prefixes.
In terms of whether it's possible to do this with Alfred, it seems like it should be, right? Alfred can individually parse each of the searches using a prefix, and then return only the results that satisfy all of them. Right?
Of course, I don't know how Alfred actually works underneath the hood, so please forgive any mistaken assumptions.
Best,
Alex