Intelligent Search
From WHMCS Documentation
The Intelligent Search in WHMCS 7.7 has been given a visual overhaul to improve the results displayed.
Results categories can be collapsed to allow only displaying the relevant results. Any categories that do not contain results are hidden and will not show. Within individual categories, the first 10 results are displayed. If more than 10 results are available, a "Show x More Results" link will display that will redo the search displaying more results for the selected category.Search as you type
The standard Intelligent Search functionality will search automatically once three characters have been entered and no typing has stopped, or return is pressed. Automatic searching can now be turned off requiring pressing return before a search will occur. Turning this off is completing per admin session, and can be done by switching the toggle at the bottom of the Intelligent Search results.
Pressing return when entering less than three numerical characters will also perform a search whether this option is on or off. It is not possible to perform an alpha search for less than three characters.
Hooks
The Intelligent Search Hook can be used to provide additional results in a search. Please see the hook documentation for how to do this.