Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
mai hoi » mai khoi, dai hoi, lai hoi
sach ky » sac ky, sach y, sach ty
van cam » van nam, van lam, van cau
su sach » so sach, vu sach
ma hoi » xa hoi, ma hoa, me hoi
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
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: su sach ky nang ((ma hoi) or (mai hoi)). hieu van cam ((xuc va) OR (tuc va)) hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((ma hoi) OR (mai hoi)). hieu van cam ((xuc va) OR (tuc va)) hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang ((ma hoi) or (mai hoi)). hieu van cam ((xuc va) OR (tuc va)) hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((ma hoi) or (mai hoi)). hieu van cam ((xuc va) OR (tuc va)) hanh vi cua triet*.