Perhaps you should try some spelling variations:
thieu hoat » thien hoat, hieu hoat, trien hoat
tinh nang » trinh nang, tin nang, tich nang
hieu soat » hieu suat, hieu hoat, hieu luat
tin dong » tien dong, tin dung, tin don
nang sat » nang suat, nang phat, nang sang
van hieu » cao hieu
sat van » sat va, hat van, hoat van
co toc » cao toc, co hoc, co doc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tin dong co toc thieu hoat ) or ( tinh nang sat van hieu soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dong co toc thieu hoat ) OR ( tinh nang sat van hieu soat ))*.