OwnCloud should do 2-way-sync
OwnCloud for Andoid can upload but not download.
Directories I create via Owncloud browser are not created or synced on Android; Directories I create on the Android OwnCloud are synced.
Mobile client configuration
Client OS (iOS, Android, ...):
ownCloud version (see ownCloud admin page):
Updated from an older ownCloud or fresh install:
ownCloud log (data/owncloud.log):
Special configurations (external storage, external authentication, reverse proxy, server-side-encryption):
The ownCloud Android app does not sync contents by default. It is design decision, motivated by the limitations in storage and network availability that mobile devices have, when compared with desktop systems.
If you need concrete files are kept in sync automatically, you can make a long press on them, open the top right menu and tap on 'Set as available offline'. The files will be marked with a yellow arrow downwards, and changes on them will be updated in 2-ways.
Besides, from version 2.2.0 of the ownCloud Android app, you can also set folders as available offline. All the files inside an available offline folder are updated automatically in 2 ways, including files in subfolders.
Hope this helps.