Perhaps you should try some spelling variations:
nam thuoc » nam thu, nha thuoc, cay thuoc
nam thuc » am thuc, nam thu, nam tu
toc sach » hoc sach, doc sach, thuoc sach
dang xay » dang van, van xay
hieu va » lieu va, hieu qua
xay hoi » xa hoi, tay hoi, cay phoi
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
vai cua » dai cua, hai cua, lai cua
hoi cua » hoi chuc
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. hieu va ((nam thuc) OR (nam thuoc)) 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. hieu va ((nam thuc) OR (nam thuoc)) 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. hieu va ((nam thuc) OR (nam thuoc)) va dau ((vai cua) or (hoi cua)) triet".
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang xay hoi. hieu va ((nam thuc) OR (nam thuoc)) va dau ((vai cua) or (hoi cua)) triet*.