Perhaps you should try some spelling variations:
luong luan » luong xuan, cuong luan, luong quang
luong quan » thong quan, duong qua
dung quan » dung quang, dung luan, dang quang
hieu soat » hieu suat, hieu hoat, hieu luat
van hieu » cao hieu
quan vi » quan li, quan tri, quan doi
vi hieu » vi dieu, va hieu, vo hieu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( tin dung quan vi hieu soat ) or ( tinh ((luong luan) or (luong quan)) van hieu soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quan vi hieu soat ) OR ( tinh ((luong luan) OR (luong quan)) van hieu soat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung quan vi hieu soat ) or ( tinh ((luong luan) or (luong quan)) van hieu soat ))*.