What is the full "get" value you're seeing in your browser's url when you see the blank output?
Paste us the entire text after the ? character. (you can replace the domain name with something fake if you want, eg: fakedomain.com)
CMD_ALL_USER_SHOW?comparison1=contains&comparison8=contains&value1=&value8=host&value=host
when searching from main page i get 1 result , its ip is server main ip when searching from admin.
CMD_ALL_USER_SHOW?value8=host&comparison8=contains&sort1=8&sort1dir=1&sort2dir=1&ipp=50
when search from search page get 6 result
i guss it search only those domains that set with reseller or admin ip.