Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
vanh dai » vanh tai, lanh dao, van dao
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va, hieu qua
van dai » van dao, van hai, can dai
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
va nam » van nam, ha nam, va nay

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 ((sach y) OR (sac ky)) dang xa hoi. hieu va nam thuc dan ((vanh dai) OR (van dai)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sac ky)) dang xa hoi. hieu va nam thuc dan ((vanh dai) OR (van dai)) cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sac ky)) dang xa hoi. hieu va nam thuc dan ((vanh dai) OR (van dai)) cua tre*.