Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
ve triet » va trien, su triet
dai danh » dai dang, dao danh, loai danh
day danh » day manh, dao danh, day dan
va tham » van tham, va cham, va thanh
hieu va » lieu va, hieu qua
sach vu » sach va, sach tu, sach uu
nang ma » tang ma, sang ma, nang cao
vu nang » vuc nang, va nang, vu dang
cua tre » cua te, cuu tre, cua triet
te sach » toc sach

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 vu nang ma hoa. hieu va tham thuc ((day danh) OR (dai danh)) dau ((cua tre) OR (ve triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach vu nang ma hoa. hieu va tham thuc ((day danh) OR (dai danh)) dau ((cua tre) or (ve triet))~".
• Adding a wildcard symbol may retrieve word variants: te sach vu nang ma hoa. hieu va tham thuc ((day danh) OR (dai danh)) dau ((cua tre) or (ve triet))*.