Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu sang » chieu sang, thieu khang, thieu quang
hoc thieu » toc thieu, hoc hien
va phuong » va thuong, cac phuong
va thong » va thuong, he thong, va cong
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap

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 - ((canh tranh) or (thanh trung)) ((va thong) OR (va phuong)) cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - ((canh tranh) OR (thanh trung)) ((va thong) OR (va phuong)) cong san toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sang - ((canh tranh) or (thanh trung)) ((va thong) OR (va phuong)) cong san toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - ((canh tranh) or (thanh trung)) ((va thong) OR (va phuong)) cong san toan cau*.