How do I (28M) get better at asking deeper emotionally validating questions to (26F) girlfriend?

r/

I’ve been dating this girl for 7 months and it’s my 1st relationship and her 4th relationship. We’ve had issues and discussions about me not being authentic, not feeling like I truly know her, her feeling mentally drained cause she has to teach me things about what being in a relationship is like, and me taking my self esteem issues to make wrong assumptions about her. I’ve been working on it but one thing that I’m still struggling with is really emotionally connecting with her. With her former ex, he just knew what the right questions to ask where and when to get her on a deeper level. For me, I’ve said stuff like “it sounds frustrating because of xyz” or “tell me more about how you feel about xyz”.

While when I’m venting, she asks me deeper questions like ““why do you think that way”, “In my opinion, I think you’re like that because of this or because of your childhood”, etc. She doesn’t want me to ask those exact types of questions to her but just using those as an example of what she views deeper emotional questions to be.

I thought of using the “5 Whys” to ask more about the root cause of her feelings during these moments but haven’t tried it yet and was wondering if there are other methods I should try.

tl;dr what types of questions to ask or how do i emotionally connect with girlfriend on a deeper level when she’s venting