If you're after a girl who can hold her side of the conversation, why not phone up a few and ask. Make it clear conversation is important for you in a meeting, and ask (tactfully) what kind of education she has, what general area her "day job" (if she has one) is in, etc. As long as you put it politely, I expect many girls will be willing to give you an answer.
As for the discerning part, as others have already mentioned I'm afraid you're just deluding yourself there