Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, su sach, te sach
dan dai » dat dai, can dai, dan dat
thuc va » thuc vat, thuc day
cua tre » cua te, cuu tre, cua triet
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 va) OR (thuc dan)) dan dai cua 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 va) OR (thuc dan)) dan dai cua 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 va) OR (thuc dan)) dan dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu ((va cham) or (va cao)) ((thuc va) OR (thuc dan)) dan dai cua tre*.