Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
tranh van » tran van, trinh van, thanh van
van nhung » van nhuong, va nhung, van hung
cong van » cong vang, cong san, song van
van chat » cao chat

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sach) or (hieu lang)) - canh tranh van nhung cong van chat va~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (hieu lang)) - canh tranh van nhung cong van chat va.
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sach) or (hieu lang)) - canh tranh van nhung cong van chat va*.