Perhaps you should try some spelling variations:
dang hanh » dang thanh, ban hanh, dang van
nam thuc » nam thuoc, am thuc, nam tu
va triet » va trien, ve triet, cua triet
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
hanh va » hang va, hanh vi
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang ma hoi. hieu ve ((nam thuc) OR (nam thu)) dang hanh va ((va triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ma hoi. hieu ve ((nam thuc) OR (nam thu)) dang hanh va ((va triet) OR (va thiet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ma hoi. hieu ve ((nam thuc) OR (nam thu)) dang hanh va ((va triet) or (va thiet))".
• Adding a wildcard symbol may retrieve word variants: su sach y nang ma hoi. hieu ve ((nam thuc) OR (nam thu)) dang hanh va ((va triet) or (va thiet))*.