Perhaps you should try some spelling variations:
tuong cong » truong cong, trong cong, tong cong
hieu sang » chieu sang, hieu lang, hieu quang
hanh hang » thanh hang, hang hang, hanh han
cong nhan » cong nhat, cong thanh, cong san
doc hieu » toc thieu, hoc thieu, hoc hien
va tuong » va thuong, va thong, xa truong
tuan cau » toan cau, quan cau, thuan cam
toan ban » van ban
tuan cu » tuan tu, quan cua, tuan thu

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sang - hanh hang va tuong cong nhan ((((tuan cau) or (tuan cu))) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - hanh hang va tuong cong nhan ((((tuan cau) OR (tuan cu))) OR (toan ban)).
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - hanh hang va tuong cong nhan ((((tuan cau) or (tuan cu))) or (toan ban))*.