Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hoc sach » hoc sinh, hoc cac, hoc anh
hieu van » hieu va, thien van, lieu va
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
cac tuc » cac toc, cac tu, cac tac
van cac » van hac, van cau, van bac
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
ma hoi » xa hoi, ma hoa, me hoi
tuc va » thuc va, truc va, tuc xa
y nang » ky nang, ly nang, v nang
vi va » vi van, vai va, vu 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) or (hoc sach)) y nang ((ma hoi) OR (mai hoi)). hieu van cac tuc va danh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (hoc sach)) y nang ((ma hoi) OR (mai hoi)). hieu van cac tuc va danh vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (hoc sach)) y nang ((ma hoi) OR (mai hoi)). hieu van cac tuc va danh vi va triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (hoc sach)) y nang ((ma hoi) OR (mai hoi)). hieu van cac tuc va danh vi va triet*.