Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
cham truc » cau truc, pham thuc, nam truc
sach van » sach han, sach va, bach van
van nang » van quang, van ban, van dong
nang dai » nang dau, nang tai, lang dai
hanh vai » hanh vi, hanh va, hanh tai
cua viet » ca viet, hoa viet, cua vat
co sach » bo sach, cuon sach, hoc sach
dai hoi » dai hoc, dai hai, dai moi
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 van nang dai hoi. hieu qua ((cham truc) OR (nham thuc)) va hanh vai cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach van nang dai hoi. hieu qua ((cham truc) OR (nham thuc)) va hanh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: co sach van nang dai hoi. hieu qua ((cham truc) OR (nham thuc)) va hanh vai cua viet*.