Opencart- Search not working

Opencart 1.5.1 is installed on the site. Here is site link [login to view URL] Problem: Search is not working. When you eanter product name at the top search bar, it works perfect but when the product name is entered in the Advance Search page, it returns No Result. Requirements: 1-Fix the issue and explain which change you did 2-Type 'open cart search issue' in your bid to consider your bid. Without this your bid will be rejected.