It's something that I'm jealous of in other applications.
If the potential search criteria are limited: say a date range, customer name and product range; you could capture the criteria in global fields. That is: ask the user to input the date range, customer and product range as variables captured from a custom dialogue. After that you can plonk them on the layout wherever you want, in whatever format you want.
But if the user just does Ctrl+F and types in their own search criteria... sorry: I can't help.
But that is possible also.
Write a script such as:
Set variable [$$DateRange ; Value: Yourtable::DateField ]
Select Layout Setup | Script Triggers
Select the OnModeExit trigger and specify that this trigger be tripped for exiting Find Mode.
Set it to perform the above script and everytime ANY find is performed on this layout, any criteria entered into YourTable::Datefield will be captured in the global variable $$DateRange.
Excellent -- this was exactly what I wanted.