Perhaps you should try some spelling variations:
dung quang » dang quang, dung quan, luong quang
quang cao » nang cao, quang nam
hieu soat » hieu suat, hieu hoat, hieu luat
luan hoan » luan van
hoan mien » hoan thien, gian mien, hoan kiem
mien soat » kiem soat, bien soan, dien hoat
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 ( trinh dung luan hoan mien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung quang cao hieu soat ) OR ( trinh dung luan hoan mien soat )).
• Adding a wildcard symbol may retrieve word variants: (( tin dung quang cao hieu soat ) or ( trinh dung luan hoan mien soat ))*.