Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh vai » hanh vi, hanh va, hanh tai
nang dai » nang dau, nang tai, lang dai
cam thuc » am thuc, nam thuc, can thuc
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
cam thu » nam thu, cac thu, ca thu
so sach » bo sach, co sach, hoc sach
dai hoi » dai hoc, dai hai, dai moi
va nang » van nang, da nang, cam nang
so sanh » do sanh
hieu ve » hieu va, hieu van

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) OR (so sanh)) va nang dai hoi. hieu ve ((cam thuc) or (cam thu)) va hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) va nang dai hoi. hieu ve ((cam thuc) OR (cam thu)) va hanh vai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) va nang dai hoi. hieu ve ((cam thuc) or (cam thu)) va hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (so sanh)) va nang dai hoi. hieu ve ((cam thuc) or (cam thu)) va hanh vai cua viet*.