How to do this..

Hi All, Need a little help with something. I've created a Search Engine Tracking tool that allows me to measure ROI from users that comes form search engines using specific keywords.. My problem is I forgot to capture a multiple of different "identifies" that tell me where the keyword is. To get the "identifier" I am using: $chunks = explode( '&', $string[query]); So for example.. Is this was my search query from the engine: http://www.google.com/search?hl=en <http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22help+me%22> &ie=UTF-8&oe=UTF-8&q=%22help+me%22 If would be entered into the Db because the keyword "identifier" is the & sign. How would I alter the above explode() code to include a bunch of "identifiers".. for example: ? K R Etc. Any thoughts? Thanks a bunch! Aaron