Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
van cua » vang cua, ban cua, dan cua
duc ban » duc tan, duc van, dua ban
lam duc » lam duoc, pham duc, nam duoc
van lam » van nam
su sach » so sach
vu sach » vu bach, vu khach
cua tre » cua te, cuu tre, cua triet
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) OR (vu sach)) ky nang ((x hoi) or (o hoi)). hieu van lam duc ban thanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky nang ((x hoi) OR (o hoi)). hieu van lam duc ban thanh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) ky nang ((x hoi) or (o hoi)). hieu van lam duc ban thanh van cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) ky nang ((x hoi) or (o hoi)). hieu van lam duc ban thanh van cua tre*.