Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
hanh de » hanh ve, hanh kem
hanh di » hanh vi, hang di, danh di
dau luc » cau luc, dau luan, dau nuoc
sach ky » sac ky, sach y, sach ty
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
van dau » van dao, phan dau
luc va » duc va, tuc va, loc va
ma hoi » xa hoi, ma hoa, me hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((ma hoi) OR (mai hoi)). hieu van dau luc va ((hanh di) OR (hanh de)) 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 dau luc va ((hanh di) OR (hanh de)) cua triet~".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((ma hoi) or (mai hoi)). hieu van dau luc va ((hanh di) OR (hanh de)) cua triet*.