orgasm

I Always orgasm with my boyfriend when im riding him and it feels so good. I orgasm various times when I'm on top of him because I love the feeling of him being deep inside. But I can't orgasm any other way. I enjoy sex so much regardless if I orgasm but I would like to try to orgasm in different positions. Any tips? Oh and when he's rubbing me down there during foreplay it always feels so good like I'm going to finish but I don't, it's like i won't "let myself" also when he's eating me out the orgasm just never happens