It is no “magic” technique but it does make the intercourse more pleasant for both male and female. The pubococcygeus muscle or PC muscle is a hammock-like muscle, found in both sexes, that stretches from the pubic bone to the coccyx (tail bone) forming the floor of the pelvic cavity and supporting the pelvic organs. Basically if you retract the PC muscle during intercourse you will increase friction between the penis and the vagina.

Here is a site which will help you learn how to use these mussels during intercourse.

You should also know that you can strengthen and give voluntary control over the pubococcygeus muscles if you do Kegel exercises.