Search finding only some results

I created a new slideshow and added images but only some of the results were found. I named images ‘norwood (1)’ through ‘norwood (25)’. I searched for ‘Norwood’ and the search found only ‘Norwood (1’) through ‘Norwood (13)’. I searched for ‘norwood (14)’ and it wans’t found, but when I searched for ’14’ it was found.

http://wordpress.org/extend/plugins/slideshow-jquery-image-gallery/