Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
van nang » van quang, van ban, van dong
hanh vai » hanh vi, hanh va, hanh tai
sach van » sach han, sach va, bach van
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
so sach » so sanh, bo sach, co sach
mai hoi » mai khoi, dai hoi, lai hoi
lai roi » lai hoi, loi roi
le nam » ly nam, he nam, le na
ve nam » he nam, va nam, te nam

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