Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, su sach, te sach
cua tre » cua te, cua triet, dua tren
dau dai » dat dai, sau dai, dau da
dan dau » danh dau, doan dau, van dau
cuu tre » cau tren, cau treo
va cham » va chat, va tham
nang xa » nang x, lang xa, nang ma
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: tu sach y nang xa hoi. hieu ((va cham) or (va cao)) thuc dan dau dai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu ((va cham) OR (va cao)) thuc dan dau dai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. hieu ((va cham) or (va cao)) thuc dan dau dai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu ((va cham) or (va cao)) thuc dan dau dai ((cua tre) OR (cuu tre))*.