Perhaps you should try some spelling variations:
ban thanh » ban hang
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
ban hanh » ban hang
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
c va » co va, cu va, _ va

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 xa hoi. hieu ve cac nuoc ((va hanh) or (((ban thanh) OR (ban hanh)))) c va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang xa hoi. hieu ve cac nuoc ((va hanh) OR (((ban thanh) OR (ban hanh)))) c va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang xa hoi. hieu ve cac nuoc ((va hanh) or (((ban thanh) OR (ban hanh)))) c va triet".
• Adding a wildcard symbol may retrieve word variants: su sach y nang xa hoi. hieu ve cac nuoc ((va hanh) or (((ban thanh) OR (ban hanh)))) c va triet*.