Perhaps you should try some spelling variations:
nang tai » hang tai, tang tai, sang tai
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu va » lieu va
thue va » thuc va, thuyet va, thuat va
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang

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) OR (hieu qua)) cam ((thue va) or (thuc vat)) nang tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. ((hieu va) OR (hieu qua)) cam ((thue va) OR (thuc vat)) nang tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang xa hoi. ((hieu va) OR (hieu qua)) cam ((thue va) or (thuc vat)) nang tai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. ((hieu va) OR (hieu qua)) cam ((thue va) or (thuc vat)) nang tai cua tre*.