Subfolders inaccessible

Hello, I do not think this issue has been raised already, although the "expandable list view" seems to be a good start...

Is your feature request related to a problem? Please describe.
The problem is that my nextcloud note folder is made up of several folders and subfolders. The synch with the android app works fine, but :
I select the folder in the left pane, only the first alphabetical subfolder is listed.
There is no apparent way for me to select the next alphabetical subfolder to access the other notes.

Describe the solution you'd like
A tree structure either in the left pane or otherwise, so that the app can reflect exactly the organization of my notes.

Describe alternatives you've considered
The only alternative to access all my notes is to select "All notes", in which case they are organized either alphabetically or according to the time of their latest modification.

Hoping I have made myself clear,
Thank you for any forthcoming update that will sort the problem,
Best,
Ph

Start in the Android app by reproducing the folder selection behavior described in the left pane, including the expandable list view mentioned in the issue. Trace how folders and subfolders are loaded and selected. Done means users can navigate every nested folder and access notes without relying on “All notes”.