Perhaps you should try some spelling variations:
qua cham » qua hai, qua cac, va cham
te sach » toc sach
sach ky » sac ky, sach y, sach ty
dua ban » dia ban, cua ban, mua ban
qua ban » cua ban, qua quan
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: te sach ky nang ((x hoi) or (xa hoi)). hieu qua cham ((dua ban) OR (qua ban)) anh d cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((x hoi) OR (xa hoi)). hieu qua cham ((dua ban) OR (qua ban)) anh d cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((x hoi) or (xa hoi)). hieu qua cham ((dua ban) OR (qua ban)) anh d cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((x hoi) or (xa hoi)). hieu qua cham ((dua ban) OR (qua ban)) anh d cua tre*.