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

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) OR (ban hanh)) d cua tre~.
• 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) OR (ban hanh)) d cua tre.
• 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) OR (ban hanh)) d cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((x hoi) or (xa hoi)). hieu qua cham dua ((ban anh) OR (ban hanh)) d cua tre*.