Making a Search Function?

Hello... I'm trying to make a search function for my site. This is how it needs to work: First, a user types in a search (ex: niagara falls). All the words then get seperated or stay together, depending on the what the user selects in the form. I can figure this out, all I have to do is use the explode() right? Second, this array needs to search against a description on the database. What I was thinking is getting the description ($description) and then exploding that into an array and then comparing all arrays against each other. I'm pretty sure there's a way easier way to do this. Could someone enligthin me? Greatly appreciate any help in advance, Dimitri Marshall