Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
qua cham » qua hai, qua cac, va cham
cham dua » chay dua, cham giua, pham duc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
dua ban » dia ban, cua ban, qua ban
ban anh » ban hanh, ban banh, ban danh
cua tre » cua te, cuu tre, dua tren
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang ((x hoi) or (xa hoi)). hieu qua cham dua ban anh d ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (xa hoi)). hieu qua cham dua ban anh d ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((x hoi) or (xa hoi)). hieu qua cham dua ban anh d ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((x hoi) or (xa hoi)). hieu qua cham dua ban anh d ((cua tre) OR (cua triet))*.