Setting to show more post when doing a catagory search?

Is there a way to adjust the number of post that are shown when doing a category search?
Such as: sparerisk.com/tools

Right now it only shows one at a time.
Will to change the code if necessary.

Thanks

To Patrick -
I don't have the ability to respond to your answer to my prior question for some reason. I just wanted you to know that your recommendation worked perfect! Thank you very much for your help.

I looked around for the code to fix the problem I described above but was unable to find it. Any thoughts?