Perhaps you should try some spelling variations:
thieu sach » thien hach, hieu cach, theo sach
chieu sach » chinh sach, chiet tach, chieu sang
manh trung » manh tung, thanh trung, manh hung
nhung cong » dung cong, thong cong, hang cong
trung cua » truong cua, trung tuan, trung cap
cua nhung » va nhung
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cao » toan cao, thai cao, than cap

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 (chieu sach)) - manh trung cua nhung cong tan than cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) OR (chieu sach)) - manh trung cua nhung cong tan than cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) OR (chieu sach)) - manh trung cua nhung cong tan than cao*.