BigCommerce site: Search not working properly

[login to view URL] Standard search field (upper part of left sidebar): Does not work when you click the search symbol (you get a blank page). The drop-down of results (without clicking) is the only way that it works. HOWEVER: In the drop-down of results, at the bottom it says "Show all results" and if you click that, you go to a blank search result page with NO results. Advanced search is not working: [login to view URL] This project is to fix these problems so that these search functions work properly. We had a customization done to the search form, which might have possibly caused this problem: Here is that project: https://www.freelancer.com/projects/bigcommerce/BigCommerce-site-Changes-Search-Form.html