Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
vanh dai » van dai, vanh tai, lanh dao
dai cuu » dai cua, dai huu
va vanh » va van, va danh, va hanh
cac duc » cac du, cao duc, cac dac
hieu va » lieu va
ty nang » ky nang, ty xang, ty hang
cuu tre » cua tre, cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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) OR (hoc sach)) ty nang x hoi. ((hieu va) or (hieu qua)) cac duc va vanh dai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) ty nang x hoi. ((hieu va) OR (hieu qua)) cac duc va vanh dai cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) ty nang x hoi. ((hieu va) or (hieu qua)) cac duc va vanh dai cuu tre*".