Looking for media(books, articles, courses, etc.) recommendations on sexual intimacy

I’ve come to realize that I’m lacking sexual intimacy when I have sex with my wife, so I figure doing some reading couldn’t hurt. Looking for anything on improving and/or maintaining sexual intimacy in relationships. It seems like most of the books I find are too either too broad on the subject of sex or too specific and not exactly what I am looking for. Any recommendations or tips are welcome, thanks!