Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cuu tre, cua triet
tinh te » kinh te, tinh tu, tinh he
va tinh » may tinh
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va
thuc va » thuc vat, thuc dan, thuc day
te cua » tue cua, le cua, de cua
bai ky » ban ky, bac ky, dai ky
sai ky » sac ky

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 ((bai ky) OR (sai ky)) nang ma hoa. ((hieu ve) OR (hieu van)) am thuc va tinh te cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((bai ky) OR (sai ky)) nang ma hoa. ((hieu ve) or (hieu van)) am thuc va tinh te cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu ((bai ky) OR (sai ky)) nang ma hoa. ((hieu ve) or (hieu van)) am thuc va tinh te cua tre*.