Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
xuc van » duc van, luc van, vuc van
dau xuc » dau xac, dau xua, dau nuoc
su sach » so sach, vu sach
vu nang » vuc nang, va nang, vu dang
hieu va » lieu va, hieu qua
va dau » va dao
v nang » va nang, van nang, voi nang
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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 ((v nang) or (vu nang)) xa hoi. hieu va dau xuc van hanh ((vi cua) OR (di cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((v nang) OR (vu nang)) xa hoi. hieu va dau xuc van hanh ((vi cua) OR (di cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((v nang) or (vu nang)) xa hoi. hieu va dau xuc van hanh ((vi cua) OR (di cua)) triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((v nang) or (vu nang)) xa hoi. hieu va dau xuc van hanh ((vi cua) OR (di cua)) triet*.