Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
trung cong » truong cong, trong cong, trung uong
tang xuan » tang quan, dang xuan, lang xuan
tang luan » dung luan
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan tap » toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc thieu sach - hanh ((tang xuan) OR (tang luan)) trung cong tac toan tap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc thieu sach - hanh ((tang xuan) OR (tang luan)) trung cong tac toan tap".
• Adding a wildcard symbol may retrieve word variants: toc thieu sach - hanh ((tang xuan) OR (tang luan)) trung cong tac toan tap*.