Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cau thuc » cau truc, cuu thuc, can thuc
thuc ban » thuoc ban, thuc dan, thu ban
ban hang » ngan hang
cua viet » ca viet, hoa viet, cua vat
so sach » so sanh, bo sach, co sach
tang ma » tang van
van cau » van dau, van hau, van chat
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y ((tang ma) OR (mang may)) hoi. hieu van cau thuc ban hang va ((cua tre) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((tang ma) OR (mang may)) hoi. hieu van cau thuc ban hang va ((cua tre) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((tang ma) OR (mang may)) hoi. hieu van cau thuc ban hang va ((cua tre) or (cua viet))".
• Adding a wildcard symbol may retrieve word variants: so sach y ((tang ma) OR (mang may)) hoi. hieu van cau thuc ban hang va ((cua tre) or (cua viet))*.