Perhaps you should try some spelling variations:
cham truc » cau truc, nham thuc, pham thuc
hoc sach » hoc sinh, hoc cac, hoc anh
van nang » van quang, van ban, van dong
nang dai » nang dau, nang tai, lang dai
qua cham » qua hai, qua cac, va cham
hanh vai » hanh vi, hanh va, hanh tai
cua viet » ca viet, hoa viet, cua vat
co sach » bo sach, cuon sach
dai hoi » dai hoc, dai hai, dai moi
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
vai cua » dai cua, hai cua, lai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((co sach) OR (hoc sach)) van nang dai hoi. hieu qua cham truc va hanh vai cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((co sach) OR (hoc sach)) van nang dai hoi. hieu qua cham truc va hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: ((co sach) OR (hoc sach)) van nang dai hoi. hieu qua cham truc va hanh vai cua viet*.