Searching the contents of HTML files for particular words

I'm developing an app for iPad which loads HTML files and so displays my content in a funny and cute manner. Now starts my nightmare, I try to search random words inside these files and don't know how. I am thinking about using some kind of Objective-C function that allows me to load the contents of each HTML file into string-like variable, then perform searches of those words using the variable's methods开发者_StackOverflow社区 (take for example doing the same in Java or C#).

Maybe this is an easy task, but I got stuck on it and would appreciate some help -- like hints, methods and functions, code fragments similar to what I am trying to do, or even some other posibilities for solving this problem I didn't think of yet.

can you use [NSString stringWithContentsOfFile:... or [NSString stringWithContentsOfURL:...?