Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
te sach » toc sach
sach ty » sach y, sach tu, sach thu
xang xa » lang xa, mang xa, ang xa
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tre » cuu tre, cua triet, dua tren
va cam » va cham, va cac, va cao
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (((cua te) OR (cua tu))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty xang xa hoi. hieu va cam thuc va hanh di ((cua tre) OR (((cua te) OR (cua tu)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (((cua te) OR (cua tu))))".
• Adding a wildcard symbol may retrieve word variants: te sach ty xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (((cua te) OR (cua tu))))*.