They are driven by the Global Search settings in the "Remedyforce Administration" Tab.
Remedyforce Administration -> Application Settings -> Global search
Add the require fields for user object to the table and that should start showing up in the console page after refresh.
This is only supported for User object within consoles as Prasanna described. For other lookups, mini page layout is not supported. Please raise an idea for other objects if you need for other lookups besides Users.