Multiple word queries

I'm trying to set up a page that will take a search from a previous pages form and make a query of a keywords table using that data. Eventually I will try to do some more elaborate things like adding the ability to group phrases together and use boolean searching, but for right now the functionality i need is thus: say someone enters a search string of "cat dog mouse rabbit" (without the qoutes) into my search box. What I need for the results page to do is to construct a query that will search through my keywords table for every instance of ANY of those words. How would you suggest I handle this?