Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhieu tang » chieu sang, hieu lang, nhiet nang
nhung cong » dung cong, thong cong, hang cong
trung dap » trung cap, trung dai, trung lap
trung dam » trung tam, trung dai, trong dam
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
toan cau » toan cao, toan ban, toan tap

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 sach) or (nhieu tang)) - hanh ((trung dap) OR (trung dam)) nhung cong van toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu sach) OR (nhieu tang)) - hanh ((trung dap) OR (trung dam)) nhung cong van toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sach) or (nhieu tang)) - hanh ((trung dap) OR (trung dam)) nhung cong van toan cau".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu sach) or (nhieu tang)) - hanh ((trung dap) OR (trung dam)) nhung cong van toan cau*.