Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
canh tinh » hanh tinh, manh tinh, nhanh tinh
toan hang » toan thang, toan hanh, toan mang
hang cong » dang cong, hang nong, bang cong
cong toan » cong tan, cong hoan, cong tuan
toan phan » thanh phan, toan ban, hoa phan

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 - ((canh tranh) or (canh tinh)) toan hang cong toan phan tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu sach - ((canh tranh) OR (canh tinh)) toan hang cong toan phan tu.
• Adding a wildcard symbol may retrieve word variants: toc thieu sach - ((canh tranh) or (canh tinh)) toan hang cong toan phan tu*.