I think I'm missing a closing table statement somewhere... But it's really difficult to judge just by looking at the code alone. Could you run the script and then output the HTML source code? Also a screenshot of the resulting page would be nice.
It might actually be a browser/CSS/styling issue, you never know. I am very reluctant to criticize the work of a 'colleague', as it seems valid code (apart from the obvious mishap with the $search_term variable, but that could happen to anyone).