Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
canh trang » canh tranh, hanh trang, banh trang
nang cong » nang song, dang cong, bang cong
trang va » tran van, hang va
cong tan » cong tac, cong san, cong thanh
phan cau » phan dau, phan cac, phan tu
toan cau » toan cao, toan ban, toan tap
va nang » van nang, da nang, cam nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sach) or (thien hach)) - canh trang va nang cong tan ((phan cau) or (toan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - canh trang va nang cong tan ((phan cau) OR (toan cau)).
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - canh trang va nang cong tan ((phan cau) or (toan cau))*.