Perhaps you should try some spelling variations:
thong cong » tong cong, thong thong, phong chong
hieu lang » chieu sang, hieu quang, nhieu tang
hanh dung » thanh dung, anh dung, hanh dong
dung cua » dung luan, dung cho
ho hieu » ho chieu, hoi hieu, nho hieu
han tap » han tai, toan tap, nhan tai
san tay » ban tay, dan tay, han tay

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - hanh dung cua ((thong cong) OR (trong cong)) thanh ((han tap) OR (san tay))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho hieu lang - hanh dung cua ((thong cong) OR (trong cong)) thanh ((han tap) or (san tay))~".
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - hanh dung cua ((thong cong) OR (trong cong)) thanh ((han tap) or (san tay))*.