Porn contains: hard and rough sex, butt, point of view, stepsister, deepthroat, ass, young, doggystyle, reverse cowgirl, cowgirl, stockings, pigtails, lingerie.
Porn contains: point of view, stepsister, eye contact, bj, cowgirl, real couple, woman fantasy, perfect tits, perfect ass, cum on pussy, doggystyle, cheating, perfect body, hard and rough sex.
I'm sure it's better to search for porn with tags rather than categories. Usually authors specify a few general categories and lots and lots of qualifying tags. Here's a list of the most popular amateur porn tags. Not enough? Below is a link to all the tags used on Hobby.porn.