Perhaps you should try some spelling variations:
tranh quang » tran quang, trinh quang, tinh quang
chieu xanh » chieu sach, chieu tinh, hieu manh
chieu sang » chieu sach, hieu lang, nhieu tang
quang dung » quang trung, ung dung, cuong dung
dung cong » dung trong
pham toan » pham tuan, pham tan, phap toan
tam toan » tap toan, tam than, tam thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((chieu xanh) or (chieu sang)) - canh tranh quang dung cong ((tam toan) OR (pham toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu xanh) OR (chieu sang)) - canh tranh quang dung cong ((tam toan) OR (pham toan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu xanh) or (chieu sang)) - canh tranh quang dung cong ((tam toan) OR (pham toan)) cau".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu xanh) or (chieu sang)) - canh tranh quang dung cong ((tam toan) OR (pham toan)) cau*.