Perhaps you should try some spelling variations:
sach tham » sach nha
thanh vai » thanh hai, thanh van, thanh tai
toc sach » hoc sach, doc sach, thuoc sach
vai cua » dai cua, hai cua, lai cua
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
va cau » van cau, va cac, va dau
luc va » tuc va, loc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tham ((nang xa) or (nang cao)) hoi. hieu va cau ((luc va) OR (duc va)) thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tham ((nang xa) OR (nang cao)) hoi. hieu va cau ((luc va) OR (duc va)) thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach tham ((nang xa) or (nang cao)) hoi. hieu va cau ((luc va) OR (duc va)) thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach tham ((nang xa) or (nang cao)) hoi. hieu va cau ((luc va) OR (duc va)) thanh vai cua tre*.