Fix a bug on a Wordpress site

I have had another developer work on my site : [login to view URL] There was an issue with the search functionality. We need the following fixed : If you search for 2291 you get the wrong image (image number 1989) If you search for [login to view URL] you get the correct image If you search for 2291 (with a space behind the last digit) you also get the correct image. The same goes for five digit numbers; If you search for 16233 you get the wrong image (image number 778425) If you search for [login to view URL] you get the correct image If you search for 16233 (with a space behind the last digit) you also get the correct image. Six digit file names are unaffected and work fine. There is an additional issue that I have just discovered, duplicate file names on the old site used to show the images with the same name and allow you to choose which one you required. The new site just shows you the file that was most recently uploaded. In a nutshell, the search function must be able to find file names of 4 digits and longer in the events folders. The search function should not use the file name extension. The search function should give the choice of file when duplicate names are encountered. I hope this makes sense...