Perhaps you should try some spelling variations:
tranh quang » tran quang, trinh quang, tinh quang
quang trong » quang truong, quang trung, quan trong
chieu sang » chieu sach, chieu xanh, hieu lang
hieu manh » chieu xanh, hieu nganh, dieu hanh
cong tan » cong tac, cong san, cong thanh
tan van » tran van, tang van, luan van

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu manh) or (chieu sang)) - canh tranh quang trong cong tan van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu manh) OR (chieu sang)) - canh tranh quang trong cong tan van ban.
• Adding a wildcard symbol may retrieve word variants: ho ((hieu manh) or (chieu sang)) - canh tranh quang trong cong tan van ban*.