Perhaps you should try some spelling variations:
quang tran » quang tuan, quang trung, quang thanh
hieu suat » hieu luat, hieu qua
kien soat » kiem soat, bien soan, kien hoa
tran van » luan van
van kien » van tien, van hien, van chien
lan van » luan van, lang van, san van
tan van » tang van, luan van, dang van

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