Perhaps you should try some spelling variations:
nang giao » nang cao
hieu nang » lieu nang, hieu lang, sieu nang
tan thanh » tran thanh, tang thanh, toan thanh
thanh va » thanh van, hanh va, thanh ha
te sach » toc sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua
x hoi » xa hoi, o hoi, 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: te sach ky nang ((x hoi) OR (x ho)). hieu nang giao duc tan thanh va cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((x hoi) OR (x ho)). hieu nang giao duc tan thanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((x hoi) OR (x ho)). hieu nang giao duc tan thanh va cua tre*.