For finding out your multiple backupduplicates(For location your file features),
1.Select the "Similar Files" Driver
2.Set the percentage of "Similar content"(Maybe 50%) in "Redefine"(Blue Font,underline).
,Click Redefine for Define Setting.
3.Finally, Search. .
4. See Scan Result as following:
PS: Backup files which are usually used for location feature are similar files, not exactly duplicate files.