Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhieu tang » chieu sang, hieu lang, nhiet nang
canh trinh » canh tranh, canh tinh, anh trinh
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, thong cong, hang cong
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 (nhieu tang)) - ((canh trinh) OR (hanh trinh)) van nhung cong van chat va~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (nhieu tang)) - ((canh trinh) OR (hanh trinh)) van nhung cong van chat va.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) or (nhieu tang)) - ((canh trinh) OR (hanh trinh)) van nhung cong van chat va".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sach) or (nhieu tang)) - ((canh trinh) OR (hanh trinh)) van nhung cong van chat va*.