Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
tieu sach » chieu sach, dien sach, te sach
tang cua » mang cua, tang luan, thong cua
hang cua » mang cua, hang ca, huong cua
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
toan tap » toan ban

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "theo tieu sach - hanh ((tang cua) OR (hang cua)) nhung cong bai toan tap~".
• Adding a wildcard symbol may retrieve word variants: theo tieu sach - hanh ((tang cua) OR (hang cua)) nhung cong bai toan tap*.