It depends if you are running NTFS (access controlled by the OS) or DMS mode(QlikView controls access to the files).
I'm assuming you run NTFS.
The it all boils down to the permissions to the QVW files. Since you are browsing via localhost then you are probably an admin and should be able to see all files. If you want hide files for some users, go to permissions for each and every file and add the users that should have access to the file so that admin and the user have access. It can be helpful to go to "advanced security settings" and disable "allow inheritable permissions..." as well on the document folder.
This can be automated via Publisher as well when distributing the files.