Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
qua cham » qua hai, qua cac, va cham
hanh lai » hanh lam, hanh tai, thanh lap
cua viet » ca viet, hoa viet, cua vat
so sach » so sanh, bo sach, co sach
dai hoi » dai hoc, dai moi
dai hai » dai han, dai tai, dai thao
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
lai cua » dai cua, hai cua, lai chau

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 ((dai hoi) OR (dai hai)). hieu qua cham truc va hanh lai cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach van nang ((dai hoi) OR (dai hai)). hieu qua cham truc va hanh lai cua viet".
• Adding a wildcard symbol may retrieve word variants: so sach van nang ((dai hoi) OR (dai hai)). hieu qua cham truc va hanh lai cua viet*.