Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
toc sach » hoc sach, doc sach, thuoc sach
xay hoi » xa hoi, cay phoi, gay thoi
tay hoi » tay ho, tao hoi, tay thai
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
thuc va » thuc vat, thuc dan, thuc day
vai cua » dai cua, hai cua, lai cua
hoi cua » hoi chuc
hieu va » lieu va, hieu qua
va nam » van nam, ha nam, va nay
va dau » va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky dang ((xay hoi) OR (tay hoi)). hieu va nam thuc va dau ((vai cua) or (hoi cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky dang ((xay hoi) OR (tay hoi)). hieu va nam thuc va dau ((vai cua) OR (hoi cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky dang ((xay hoi) OR (tay hoi)). hieu va nam thuc va dau ((vai cua) or (hoi cua)) triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang ((xay hoi) OR (tay hoi)). hieu va nam thuc va dau ((vai cua) or (hoi cua)) triet*.