passing values between user controls..

Question

I'm developing a search functionality..

In header user control (headercontrol.ascx), search box exists, so user can search from any page as user control is in master page. 

I want do display search results in testresults.ascx which is in testresults.aspx.

testresults.aspx is embedded in master.master page and it includes headercontrol.ascx.

if user enters search word, I want to pass search word from headercontrol.ascx to testresults.ascx as I need to pass the search word to DB query which exists in testresults.ascx. when user enters search word, the page is getting submitted through java script as I'm using Jquery to display intellisence.

please help how to pass search key word from headercontrol.ascx to testresults.ascx.

Thanks in advance..