Perhaps you should try some spelling variations:
dung quang » dang quang, dung quan, dung luan
luong quan » thong quan, duong qua
quang cao » nang cao, quang nam
hieu soat » hieu suat, hieu hoat, hieu luat
chan kiem » phan kiem, chan kim, chat kiem
kiem soat » kiem toan
tin » tinh

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 cao hieu soat ) or ( minh ((luong quang) OR (luong quan)) chan kiem soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quang cao hieu soat ) OR ( minh ((luong quang) OR (luong quan)) chan kiem soat )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tin dung quang cao hieu soat ) or ( minh ((luong quang) OR (luong quan)) chan kiem soat ))".
• Adding a wildcard symbol may retrieve word variants: (( tin dung quang cao hieu soat ) or ( minh ((luong quang) OR (luong quan)) chan kiem soat ))*.