Perhaps you should try some spelling variations:
luong quang » luong quan
tinh luong » tinh huong, dinh luong, minh luong
dung quang » dang quang, dung quan, dung luan
quang van » quang ban, quan van, quang uan
hieu soat » hieu suat, hieu hoat, hieu luat
quang can » quang chan, quang cao, quang ban
kiem soat » kiem toan
van hieu » cao hieu
can kiem » van kiem, can kim, toan kiem

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 quang van hieu soat ) or ( tinh luong quang can kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quang van hieu soat ) OR ( tinh luong quang can kiem soat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung quang van hieu soat ) or ( tinh luong quang can kiem soat ))*.