Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
tham thong » pham thuong, than thuong, thoai thong
thong cong » trong cong, tong cong, thong thong
cong tham » chong tham, cong thai, hong tham
hieu van » hieu va, thien van, lieu va
cong dan » cong san, cong tan, huong dan
dan chan » dan gian, dan ca, van chat
chan ca » chac ca, chan ta, nhan 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 ((hieu van) or (chieu sach)) - thanh cong tham thong cong dan chan ca~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu van) OR (chieu sach)) - thanh cong tham thong cong dan chan ca.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu van) or (chieu sach)) - thanh cong tham thong cong dan chan ca*.