Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tran » hanh trang, thanh tran, hanh tram
nang cong » nang song, dang cong, bang cong
tran van » luan van
van nang » van quang, van ban, van dong
cong dan » cong san, cong tan, huong dan
toan tai » toan tap, doanh tai, toan ban
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: ho ((chieu sach) or (hieu lang)) - hanh tran van nang cong dan ((toan tai) or (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (hieu lang)) - hanh tran van nang cong dan ((toan tai) OR (toan cao)).
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (hieu lang)) - hanh tran van nang cong dan ((toan tai) or (toan cao))*.