Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, thanh san
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
tu sach » thu sach, su sach, te sach
duc ban » duc tan, duc van, dua ban
lam duc » lam duoc, pham duc, nam duoc
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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 ky nang o hoi. ((hieu van) or (thien van)) lam duc ban ((thanh tai) or (doanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang o hoi. ((hieu van) OR (thien van)) lam duc ban ((thanh tai) OR (doanh tai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang o hoi. ((hieu van) or (thien van)) lam duc ban ((thanh tai) or (doanh tai)) cua tre*.