If your partners have had their own orgasms and left you wanting then you may very possibly have been with jerks. But on the other hand it may not be entirely their fault if you do not know your own body. Experiment with masturbation until you achieve an orgasm by yourself and know what to expect. It will help you when you have sex with others.
I know that it took a long before I had my first orgasm. Hell, I didn't even like sex for a long time. It took time, experimentation, practice, and finding out what worked for me.
So you have had sex with guys and all of them did not care if you had an orgasm too. Well I hate to tell you this but there are men like that all ages.
If you think they just do not understand and you are willing to teach them, then you have a future with a guy.. Lots of men think they know all the answers. If you are meeting this kind of guy just move on. There a lots of guys who will want you and I promise there are guys that know if you cum too they can have just about anything they want from a woman.
I am assuming you cum by Masturbation though.
I would say to give yourself time. You might need longer sex or to be more aroused, or any number of things that you really need not worry about... just enjoy what you can. Sex can always be worked at, and the partners may or may not be the reason or contribute ~they may not be as into satisfying or as skilled. A man going down and staying down (if done well) can be VERY VERY exciting and a nice way to orgasm, TOO. Just give yourself time.
You may or may not be more at ease and relaxed by rubbing yourself and masturbating to climax if you have not experienced and orgasm at all yet (?) Maybe~ start there.
I didn't orgasm until I was nearly 19, and had been active years before that. It's possible you have been on the verge and thought you needed to pee, or maybe even possible that you have in fact had one, and just didn't know it. Not everyone has earth shattering orgasms. Spend some time with your own body, then when you are ready to be with another partner show him how to do it for you.
Are you comfortable with your body? You're young, just take the time to explore & find out what you enjoy. Experiment on your own and relax. And never be ashamed of what excites you and what turns you off.