Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
hoc thieu » toc thieu, hoc hien
cong hoan » cong hoa, dong hoa, cong san
cong cua » cong cu, dong cua, huong cua
hoan van » hoang van, hoa van, doan van
thang ca » thang cua, hang ca, tang ca
thai cua » than cua, tai cuc, tri cua

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 - thanh cong cua cong hoan van ((thang ca) or (thai cua))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - thanh cong cua cong hoan van ((thang ca) OR (thai cua)).
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - thanh cong cua cong hoan van ((thang ca) or (thai cua))*.