Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
thanh trung » thanh tung
xuan truong » duong truong
thieu sang » chieu sang, thieu quang, hieu lang
xa truong » cac truong
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan ban » van ban

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) or (thieu khang)) - thanh trung ((xa truong) or (xuan truong)) cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (thieu khang)) - thanh trung ((xa truong) OR (xuan truong)) cong san toan ban.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) or (thieu khang)) - thanh trung ((xa truong) or (xuan truong)) cong san toan ban*.