Perhaps you should try some spelling variations:
chien soat » thien hoat
hieu suat » hieu luat, hieu qua
tinh dung » tin dung, tinh quang, tinh huong
van chien » van hien, van hieu, van tien
dung lan » dung land, dung lam, dung san
lan cao » lang cao, lan cho, nang cao
luan » quan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( trinh dung lan cao hieu suat ) or ( tinh dung luan van chien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( trinh dung lan cao hieu suat ) OR ( tinh dung luan van chien soat )).
• Adding a wildcard symbol may retrieve word variants: (( trinh dung lan cao hieu suat ) or ( tinh dung luan van chien soat ))*.