A contraction of "nookie" and "book smart". Having the natural ability to read women perfectly in order to get laid.
a) Charlie is too damn nook smart for his own good. He'll never be someone's Mr. Right, but somehow always manages to be Mr. Right Now.
b) Just like how being book smart doesn't help on the streets, it's important to note that being nook smart isn't helpful in long term relatipnships.