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
dong cong » duong cong, dung cong, dang cong
tac thanh » bac thanh, cac thanh, tcc thanh
tac than » tam than, tac nhan, bac thanh
tung ha » trung ha, dung ha, tung ho
ha dong » hoat dong, van dong

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 ha dong 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 ha dong cong ((tac than) OR (tac thanh)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (hieu cach)) - thanh tung ha dong cong ((tac than) or (tac thanh)) cau*.