Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
tranh cua » doanh cua, manh cua
dung cong » dung trong
cua dung » cua dang, cua dong, qua dung
cong tan » cong tac, cong san, cong thanh
than tap » toan tap, phan tap, than cap
han tap » han tai, toan tap, nhan tai

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 (thien hach)) - canh tranh cua dung cong tan ((than tap) or (han tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - canh tranh cua dung cong tan ((than tap) OR (han tap)).
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - canh tranh cua dung cong tan ((than tap) or (han tap))*.