Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
cau tren » cu tren, dau tren, ca tren
cuu tre » cua tre, cau treo
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
te sach » toc sach
hieu va » lieu va, hieu qua
ty hang » ly hang, ty xang, thi hang
ty ang » ty xang, ty anh
va cam » va cham, va cac, va cao

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: te sach ((ty ang) OR (ty hang)) xa hoi. hieu va cam thuc va hanh di ((cuu tre) OR (cau tren))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty ang) or (ty hang)) xa hoi. hieu va cam thuc va hanh di ((cuu tre) OR (cau tren))~".
• Adding a wildcard symbol may retrieve word variants: te sach ((ty ang) or (ty hang)) xa hoi. hieu va cam thuc va hanh di ((cuu tre) OR (cau tren))*.