Perhaps you should try some spelling variations:
qua cham » qua hai, qua cac, va cham
su sach » so sach, vu sach
duc ban » duc tan, duc van, duc man
dua ban » dia ban, cua ban, qua ban
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
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: su sach y nang ((x hoi) or (xa hoi)). hieu qua cham ((duc ban) or (dua ban)) anh d cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((x hoi) OR (xa hoi)). hieu qua cham ((duc ban) OR (dua ban)) anh d cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((x hoi) or (xa hoi)). hieu qua cham ((duc ban) or (dua ban)) anh d cua tre*.