Perhaps you should try some spelling variations:
tinh dung » trinh dung, tin dung, tinh quang
hieu suat » hieu luat, hieu qua
mang dung » manh dung, dang dung, mang cung
tin mang » tin nang, ninh mang, tien manh
dung van » duong van, dung va, dang van
van dien » van tien, van hien, van kien
dien so » bien so, dien o, dien co

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

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