You have a lot of files (thousands or millions) in a directory and your FTP client do not show all of them? Find out that the issue has nothing to do with your FTP client.
The FTP server is the one that decides how many files to show.
For example for pure-ftp (a very popular FTP server for cPanel servers) the limit is 10000. You can modify this value anytime according to your needs by editing the file /etc/pure-ftpd.conf and set the maximum number of files to be displayed:
# 'ls' recursion limits. The first argument is the maximum number of # files to be displayed. The second one is the max subdirectories depth LimitRecursion 10000 8
Don’t forget to restart the FTP server (in our case for pure-ftp server):
root@web [~]# service pure-ftpd restart