Perhaps you should try some spelling variations:
nam thuc » nam thuoc, nam thu, nam tu
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tre » cuu tre, cua triet, dua tren
tu cao » cu cao, tu cac, vu cao
ma hoi » mai hoi, xa hoi, ma hoa
cua te » cua tu

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 cao ky nang ma hoi. hieu va ((nam thuc) OR (am thuc)) va hanh di ((cua tre) OR (cua te))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cao ky nang ma hoi. hieu va ((nam thuc) or (am thuc)) va hanh di ((cua tre) OR (cua te))~".
• Adding a wildcard symbol may retrieve word variants: tu cao ky nang ma hoi. hieu va ((nam thuc) or (am thuc)) va hanh di ((cua tre) OR (cua te))*.