Most females do not have a REAL orgasm for a majority of their life until they reach their peak which is about 3-5 years before they reach menopause.

Don't take it on your manhood. It's their fault they can't have an orgasm through penis or oral stimulation.

Try using a finger on her while your fucking her.

And sometimes an orgasm is more than just stimulating the clitoris. It can do with various other little things..like the way you treat her..the way you move around her body, the things you say to her and the speed and velocity of the sex. The position can also be a factor.

If all options don't work from any advice you achieve it is most likely that these girls are just not able to recieve an orgasm.

And don't forget, just because a girl cums does not mean she has orgasmed.

Guys though, they are different, each time they orgasm they ejaculate and vice versa. Even if there is nothing to shoot you still cum.

The female composure is a very versatile and touchy subject.