Perhaps you should try some spelling variations:
van nang » van quang, van dong, van dung
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
so sach » so sanh, bo sach, co sach
vu nang » vuc nang, va nang, vu dang
van cam » van nam, van lam, van cau
xuc van » duc van, luc van, vuc van
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((vu nang) or (((van nang) OR (van ban)))) xa hoi. hieu van cam xuc van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((vu nang) OR (((van nang) OR (van ban)))) xa hoi. hieu van cam xuc van hanh vi cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((vu nang) or (((van nang) OR (van ban)))) xa hoi. hieu van cam xuc van hanh vi cua vat".
• Adding a wildcard symbol may retrieve word variants: so sach ((vu nang) or (((van nang) OR (van ban)))) xa hoi. hieu van cam xuc van hanh vi cua vat*.