Recover certain files from Time machine from previous Mac
The following worked with my Synology NAS:


Browse to the network drive in Finder
Double-click on the sparse bundle file for the computer you want to access.  
Click on the "Time Machine Backups" disk image in Finder (added to the left-hand pane by step 2 above).
Open the backups.backupsdb folder inside this disk image.
Continue as per previous comments.