Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
thanh tung » thanh cong
hieu lang » chieu sang, hieu quang, nhieu tang
vat dung » van dung, viet dung, mat duong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap
va dung » van dung, va duong, va ung

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 ((chieu xanh) OR (hieu lang)) - thanh tung ((va dung) OR (vat dung)) cong tap toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu xanh) or (hieu lang)) - thanh tung ((va dung) OR (vat dung)) cong tap toan cao~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu xanh) or (hieu lang)) - thanh tung ((va dung) OR (vat dung)) cong tap toan cao*.