<human>: Could you distill the essence of the text into 1-3 sentences?

I (25F) am in a great 6-month relationship with a 30M.  He's a positive communicator, calls me out when he has a problem or his feelings hurt by something I've done, and has a way of telling criticism without hurting me.  Last week, I came across his dirty secret- he has 5 relationship/communication books thrown in his closet (didn't catch the titles).

I asked if I could borrow one, and he immediately said no. He was embarrassed and defensive, so I dropped the subject immediately.  However, this had made me think over if I should study some books in this genre.  He's a much better partner than I (in my biased opinion), and I'm certain he's used skills from these books on me.  However, I don't want to appear like I'm trying to learn/subvert his methods. I'd appreciate any advice on:

- How to approach the issue of me wanting to read relationship books without appearing to mock his usage

- What relationship books have worked well for you?  I'm assuming the famous  "Five Love Languages" would be a good start
<bot>: He's used relationship books successfully, I'd like to do so without it turning into a pissing contest of positive communication