Time Machine backup with empty folders

Hi,

my last two time machine backups (in the same day) have a particular fault that made me lost all the work I did from the previous backup. All the new folders created since the last backup are there but empty. If there is a new file in an old folder, the backup worked fine. But all the content I inserted in new folders are gone.

Now, I don't know if I can keep trusting Time Machine or not...

Luis