It is better to hide tmp/usr/lib/var folders via the conf file(when accessing ftp) so that these folders will not be accessed by the users.

If it is proftpd, find out the proftpd.conf

Add the following to the proftpd.conf file:

Enter the directory path near to “<Directory >”, like “<Directory /var/www/vhosts/domainName/httpdocs/folder>”

After modification, restart the FTP.