Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, theo sach
thanh tung » thanh cong
hieu cach » hieu cac, chieu sach, hieu ca
dang cong » dung cong
tac thanh » bac thanh, cac thanh, tcc thanh
tung cua » trung cua, tuong cua, dung cua
cua dang » cua cong, cua ban
tac than » tam than, tac nhan, bac thanh

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 (hieu cach)) - thanh tung cua dang cong ((tac than) OR (tac thanh)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (hieu cach)) - thanh tung cua dang cong ((tac than) OR (tac thanh)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (hieu cach)) - thanh tung cua dang cong ((tac than) OR (tac thanh)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (hieu cach)) - thanh tung cua dang cong ((tac than) OR (tac thanh)) cau*.