Perhaps you should try some spelling variations:
duong luan » dung luan, dong luan, duong quan
quan quan » quan quang, qua quan, quan luan
kien soat » kiem soat, bien soan, kien hoa
hieu soat » hieu suat, hieu hoat, hieu luat
tin quan » tinh quang, trinh quan, lien quan
quan van » quan va, quan luan, quan doan
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 quan quan van kien soat ) or ( dinh duong luan van ((hieu soat) or (hieu qua)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin quan quan van kien soat ) OR ( dinh duong luan van ((hieu soat) OR (hieu qua)) )).
• Adding a wildcard symbol may retrieve word variants: (( tin quan quan van kien soat ) or ( dinh duong luan van ((hieu soat) or (hieu qua)) ))*.