Lack of Orgasm

I have no problem getting off with a little vibration or the touch of my own fingers. But I want the natural, internal orgasm that I hear so many stories about. How can I achieve this without changing my medications that I have been on for more than 10 years. I believe they may be a part of the cause of the hard ship I am experiencing. It's very frustrating to only have an orgasm about once a out of every 15 times I have sex with my boyfriend.