A girl will only invest in the conversation once she's hooked. You have to do the conversational work until this point (we call it "crossing the assumption bridge") - the Capture and Attraction phases of the Daygame Blueprint.
Once you notice a hook (she crosses her legs, plays with her hair, asks you a question) then ask some of the big open questions from above. If she asks you a question, answer it but then quickly relate it back to her. We follow the 90/10 rule of investment.