How To Give Any Woman orgasm

My girlfriend usually does not get an orgasm when we have sex. What am I doing wrong? How should I do to give a woman an orgasm? Tell me more about female orgasm.
Answer:
Female orgasm not the same as male orgasm
For most men, sex ends with an orgasm. This is very important for most men. And after the orgasm, most men are satisfied and not willing to participate in active sex any more for some time. All this is different for women.