[Unwire]

I would like to perform a search that matches a search term across multiple categories. I've searched the forums but have not been able to find a solution. Has this been done? Any idea how I might accomplish this?

URL-based search is acceptable (no need to redesign search page).. So far I'm able to perform a search within a single category with the following URL:

/search.php?mode=search&substring=&including=all&by _title=on&by_descr=on&by_sku=on&categoryid=23&sear ch_in_subcategories=on

Any thoughts on how I might expand this to search multiple categories? (eg: 23 AND 24).

Thanks in advance,
Chris.