Perhaps you should try some spelling variations:
luc quan » luc luan, tac quan, qua quan
quoc ban » quoc bao, quoc lan, quoc quan
hieu va » lieu va, hieu qua
su sach » so sach, vu sach
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
y nang » ky nang, ly nang, v nang
anh ve » hanh ve, anh va, anh viet
ve cua » le cua, de cua, te cua
o hoi » co hoi, o hoc, o hai
x hoi » xa 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: su sach y nang ((x hoi) or (o hoi)). hieu va cam ((quoc ban) or (luc quan)) anh ve cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((x hoi) OR (o hoi)). hieu va cam ((quoc ban) OR (luc quan)) anh ve cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((x hoi) or (o hoi)). hieu va cam ((quoc ban) or (luc quan)) anh ve cua tre*.