Make sure that the edited NDMP Client under the NDMP Plugin within the Backup window has the "Use UTF-8 conversions" not selected.
Make sure the NDMP backup job Backup Options tab has the "Request unicode file information" selected and then click on the traffic light to save and schedule the backup job.
If the reverse is setup, then you will only be able to see the first letter of the volume/file in the Restore window and might not be able to use the search function for a file or volume.
Note: After upgrading the OnTap version on a NetApp Filer, please reboot the Filer otherwise you will experience backup performance issues.