Perhaps you should try some spelling variations:
quang tran » quang tuan, quang trung, quang thanh
dung lquan » dung luan, dung quan, dung quang
lquan van » luan van, quan van, luan va
hieu suat » hieu luat, hieu qua
van hieu » cao hieu
van kiem » va kiem, van hien, tac kiem
van kien » van tien, van hien, van chien

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 lquan van hieu suat ) or ( tinh quang tran ((van kiem) OR (van kien)) toan ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung lquan van hieu suat ) OR ( tinh quang tran ((van kiem) OR (van kien)) toan )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tin dung lquan van hieu suat ) or ( tinh quang tran ((van kiem) OR (van kien)) toan ))".
• Adding a wildcard symbol may retrieve word variants: (( tin dung lquan van hieu suat ) or ( tinh quang tran ((van kiem) OR (van kien)) toan ))*.