Perhaps you should try some spelling variations:
thanh trung » thanh tung
tang sach » mang sach, sang sach, tvqg sach
nang sach » mang sach, sang sach, ngan sach
van dung » van dong, xay dung, tin dung
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: hoc ((tang sach) OR (nang sach)) - thanh trung ((tran quang) or (van dung)) cong tac toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((tang sach) OR (nang sach)) - thanh trung ((tran quang) OR (van dung)) cong tac toan tap*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((tang sach) OR (nang sach)) - thanh trung ((tran quang) or (van dung)) cong tac toan tap*".