whois c21school.edu.kh/kcfinder/themes/slotjoker.php
c21school.edu.kh/kcfinder/themes/slotjoker.php
checking....c21school.edu.kh/kcfinder/themes/slotjoker.php
$ whois c21school.edu.kh/kcfinder/themes/slotjoker.php
No whois server is known for this kind of object.