Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, chieu tinh
hieu quang » thieu quang, hieu quan, hieu qua
nhung cong » dung cong, thong cong, hang cong
hanh tran » hanh trang, thanh tran, hanh tram
van nhung » van nhuong, va nhung, van hung
tran van » luan van
toan cao » toan ban
toan tap » toan ban

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 quang)) - hanh tran van nhung cong ty ((toan cao) OR (toan tap))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu xanh) or (hieu quang)) - hanh tran van nhung cong ty ((toan cao) OR (toan tap))~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu xanh) or (hieu quang)) - hanh tran van nhung cong ty ((toan cao) OR (toan tap))*.