Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh vai » hanh vi, hanh va, hanh tai
cam thuc » am thuc, nam thuc, cam thu
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
lai hoi » dai hoi, lai hoa, lai roi
mai doi » moi doi, mai hoi, mai khoi
co sach » bo sach, cuon sach
vai cua » dai cua, hai cua, lai cua
ve cam » ve cham, ve cac, va cam
v nang » va nang, vu nang, van nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (co sach)) v nang ((mai doi) or (lai hoi)). hieu ve cam thuc va hanh vai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (co sach)) v nang ((mai doi) OR (lai hoi)). hieu ve cam thuc va hanh vai cua vat.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (co sach)) v nang ((mai doi) or (lai hoi)). hieu ve cam thuc va hanh vai cua vat*.