In addition to VPIP, there are a lot of things you can pay attention to in order to narrow villain's range. Below are just some examples, there are alot more.
How aggressive is villain? An aggressive villain tends to not call a lot, he tends to bet or raise. If an aggressive villain stays in a hand but hasn't raised, he's probably drawing, floating, or playing a medium hand. You can't necessarily narrow a passive villain this way, they will call w the nuts as well as medium hands. A river shove from a passive villain is more likely the nuts than a bluff, but for an agg villain is more frequently a bluff (that's not saying it's the majority of the time).
How often does villain ch/r? If it's very rare and you get ch/r'd, fold.
Is villain positionally aware? If his VPIP is the same across ep, mp, and lp, he's not positionally aware, and playing weaker hands from ep (sc's for example). If his VPIP is narrow in ep and wide in lp, and he opens utg, he's playing a stronger range than someone who's VPIP is the same across positions.
How often does villain 3bet? The more frequently villain 3bets, the more likely some of his 3bets are weak.