Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hieu sach » chieu sach, hieu cach, dien sach
van thanh » van tuan
ban thanh » ban hanh, ban hang
doc hieu » toc thieu, hoc thieu, hoc hien
tang cua » hang cua, tang luan, thong cua
mang cua » manh cua, dung cua, ban cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sach - hanh ((tang cua) or (mang cua)) nhung cong ((van thanh) OR (ban thanh)) hai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sach - hanh ((tang cua) OR (mang cua)) nhung cong ((van thanh) OR (ban thanh)) hai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu sach - hanh ((tang cua) or (mang cua)) nhung cong ((van thanh) OR (ban thanh)) hai".
• Adding a wildcard symbol may retrieve word variants: doc hieu sach - hanh ((tang cua) or (mang cua)) nhung cong ((van thanh) OR (ban thanh)) hai*.