Stop creating copy of your file to backup versions of your document, do that simply with ezVersions !!!
To install ezVersions search for « ezVersions » in the Add-on store or go directly to the listing by following this link : install ezVersions.
Once installed got to the Add-on menu and open ezVersions
In the Add-on you will have access to the previous versions you saved and to save a new one you just have to enter a name and click on « Save ».
Now for each version you can :
You can save how many versions you want in the Add-on.