Perhaps you should try some spelling variations:
cao hoat » cac hoat, co hoat, cao chat
tu sach » thu sach, su sach, te sach
tinh di » tinh doi, trinh di, tinh da
chuc va » thuc va
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
di cua » dai cua, doi cua, de cua

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