Perhaps you should try some spelling variations:
thong cong » tong cong, thong thong, phong chong
thieu sang » chieu sang, thieu khang, thieu quang
hoc thieu » toc thieu, hoc hien
hanh tam » thanh tam, nhanh tam, hanh tram
san toan » van toan, dan toan, manh toan
toan ban » van ban
tam van » nam van, dam van, tom van

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sang - hanh tam van ((thong cong) or (trong cong)) san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - hanh tam van ((thong cong) OR (trong cong)) san toan ban*.