Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
thien hach » thien thanh, hien hanh
nang cong » nang song, dang cong, bang cong
cong tan » cong tac, cong san, cong thanh
cong va » dong va, cong ha, cong tac
va nang » van nang, da nang, cam nang
tan tho » tap tho, can tho, dan tho
tho cac » cho cac, tho ca, thong cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sach) or (thien hach)) - thanh cong va nang cong tan tho cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (thien hach)) - thanh cong va nang cong tan tho cac*.