Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
thuc day » thuc dan, thuc vat
va triet » va trien, ve triet, cua triet
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu le » hieu ve, hieu he, hieu ly
hanh va » hang va
le nam » ly nam, he nam, le na
thiet » thieu

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: so sach ky nang xa hoi. hieu le nam thuc day ((hanh va) OR (hanh vi)) ((va triet) OR (va thiet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang xa hoi. hieu le nam thuc day ((hanh va) OR (hanh vi)) ((va triet) or (va thiet))~".
• Adding a wildcard symbol may retrieve word variants: so sach ky nang xa hoi. hieu le nam thuc day ((hanh va) OR (hanh vi)) ((va triet) or (va thiet))*.