Perhaps you should try some spelling variations:
thieu nien » thien nhien
nien cac » vien cac, dien cac, bien cac
hanh dai » hanh tai, hanh dao, vanh dai
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
cua tre » cua te, cua triet, dua tren
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
xay hoi » xa hoi, tay hoi, cay phoi
ty hang » ly hang, thi hang, thu hang
cuu tre » cau tren, cau treo

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 ((ty xang) or (ty hang)) xay hoi. thieu nien cac nuoc va hanh dai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty xang) OR (ty hang)) xay hoi. thieu nien cac nuoc va hanh dai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty xang) or (ty hang)) xay hoi. thieu nien cac nuoc va hanh dai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty xang) or (ty hang)) xay hoi. thieu nien cac nuoc va hanh dai ((cua tre) OR (cuu tre))*.