On Common Grid view Search Textbox/ Option Not Filtering data in record set.
E.g. in new enhanced Timesheet 'Select Task' Option we can't Project name using direct search Option.
User needs to use Filter-Funnel and select Investment Name field to search on Project name which is confusing for the non-technical users.
The same behavior is on Custom Object Common Grid which causing lot of confusion for users and they can't search unless user select specific filed.
Our understanding is Search Option should work across the records set of an object or List.
Release : 16.0.0
By design, the search box will search by object name and/or object id and not all columns.
This is to avoid a performance issue by searching using wild cards across many columns.