TL;DR: make her open up about her sexual preferences

I had a date at the weekend, stayed there over night, fucked her few times and want to keep her for fwb. But, before sex, I always asked her what she wants, what’s her favourite and so on… it’s just better to ask and care about her preference. She always just said that she can go with anything and never said what she is into, so I was the one saying what I want and therefore it was kinda one-sided. She seemed to enjoy, but never came. How to get it out of her ? If I want to keep her for fwb, i also need to make her satisfied and naturally it would feel better for me as well, but she never talks about her personal sexual experience.