Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
vanh dai » van dai, vanh tai, lanh dao
cau treo » cau theo, cau tren, cau triet
truc va » thuc va, thuc vat, trung va
va vanh » va van, va danh, va hanh
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
va cai » va cac, va bai, va dai
y nang » ky nang, ly nang, v nang
va cao » va cac, va co, va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y nang xa hoi. hieu ((va cai) or (va cao)) truc va vanh dai ((cua tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang xa hoi. hieu ((va cai) OR (va cao)) truc va vanh dai ((cua tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: thu sach y nang xa hoi. hieu ((va cai) or (va cao)) truc va vanh dai ((cua tre) or (cau treo))*.