Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cuu tre, cua triet
tinh ve » trinh ve, tinh ven, dinh ve
va tinh » may tinh
hieu ve » hieu va
thuc va » thuc vat, thuc dan, thuc day
ve cua » le cua, de cua, te cua
tu sai » tu bai, tu san, tu cai
sai ky » sac ky
ma hoi » mai hoi, ma hoa, me hoi

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky nang ((ma hoi) OR (xa hoi)). ((hieu ve) OR (hieu van)) am thuc va tinh ve cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky nang ((ma hoi) or (xa hoi)). ((hieu ve) OR (hieu van)) am thuc va tinh ve cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sai ky nang ((ma hoi) or (xa hoi)). ((hieu ve) OR (hieu van)) am thuc va tinh ve cua tre*.