Perhaps you should try some spelling variations:
thanh hoa » thanh pho
thanh tai » thanh hai, thanh toan, doanh tai
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
cac ban » cac dan, cac van, can ban
hau cac » hau can, hay cac, phan cac
van hau » van ha, van hai, van dau
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
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: tu sach y nang ((x hoi) or (o hoi)). hieu van hau cac ban ((thanh tai) or (thanh hoa)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (o hoi)). hieu van hau cac ban ((thanh tai) OR (thanh hoa)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) or (o hoi)). hieu van hau cac ban ((thanh tai) or (thanh hoa)) cua tre*.