Sophos Secure Mail APP / IOS / Search mail in subfolders


is it possible to enable / configure a "global" mail search include the subfolders?

Currently I have no chance to search a mail in subfolders - only the searched mails in the marked folder will be displayed.

Its a little bit tricky to explain that topic to my customers (a lot of this guys has hundreds of subfolders), because any other mail client has this possibilty...

Any advice / solutions?!

Our currenty infrastructre:

Server Version SMC 9.5.2
IOS Devices 12.4.5 & 13.3
Sophos Secure Mail App - Version 7.97.2

BR Paddy