Filter Results Properly -- SQL

I am setting up a site that has a number of filters to filter certain results. Right now the filters will return results for only those that match ALL of the boxes ticked. I want the results returned to reflect ANY of the boxes ticked. In other words, for the price option, I have "Under $1,000" and $1,000-$2,000". If the user ticks both of these boxes, they will get no results (since the price can never be both under $1,000 and between $1,000 and $2,000). I want the results to show all of those results that are BOTH under $1,000 and between $1,000 and $2,000 (if the user ticks BOTH of those boxes). Here is the link: [login to view URL] One forum said I could "return an array with indeces that map with the supposedly variable names" or I could "set each column data returned from query into variables." I would like to hire someone to make the filters work properly. Please note that this is a wordpress-based site ([login to view URL]).