Making WP_Query work with Search

I am currently working on a site that has multiple WP_Query declarations that are active depending on the current category. I’d like to make the search function search that query and display posts that only include the search term/string. I’d also like the search to stay on the category permalink location. I have looked around for help, but nothing seems to work. Is this possible? or does the search have to go to a different location.

At the moment, the search term is pretty much ignored and all posts in that category are displayed.

Any ideas on what might cause this problem, or can someone post an example of a custom WP_Query working with a category search?

That would be wonderful!