In this case, "have some" of something means "be more like a typical person who has" that thing. For example, it's common to say something like, "don't be so scared. Have some courage." It means, be more courageous. Hormones partly control our sexual urges. Joey is saying that Ross should go look at women and act like a man who has sexual urges, rather than stay home and feel sad for himself. It's not a common thing to say. It works in that one situation.

Or "Be a man!"

I agree with Robert - it's not something I see written like that. Perhaps something along the lines of "Man up!", "Grow a pair!", etc. The meaning is just along the lines of Joey encouraging Ross to be more masculine and pursue sexual activities instead of moping around.