There is an island off the coast of Ireland where married couples average one orgasm a month, whether they need it or not. It is a very hard number to calculate. Just try to enjoy it. You have to do those things that will give her one. This is not just double-talk.
Every woman is different.
Most women like common body parts stimulated. If your wife can have an orgasm by herself, that is good news. If your wife can't have an orgasm under any circumstance, then first she needs to learn how to do that, which is best learned alone. You need to try a bridging technique where you take the orgasm from one situation and bring it into the intercourse situation. This is not really complex, but does take a little professional intervention.