Perhaps you should try some spelling variations:
tieu sach » chieu sach, dien sach, te sach
hanh dong » anh dong, ha dong
cong cong » cong dong, trong cong, dung cong
dong cua » dung cua, cong cua, huong cua
cong tac » cong ty
tran tap » toan tap, tran tuan, trang tai
tran tan » tran tuan, tran van, tran thanh

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo tieu sach - hanh dong cua cong cong tac ((tran tap) OR (tran tan))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo tieu sach - hanh dong cua cong cong tac ((tran tap) OR (tran tan))*".