Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
tuong cong » truong cong, trong cong, tong cong
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tran » hanh trang, thanh tran, hanh tram
van tuong » van truong, van thuong, van duong
tran van » luan van
cong van » cong vang, cong san, song van
van chat » cao chat
van van » van ban, tan van, san van

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

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