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
sach ky » sac ky, sach y, sach ty
vu sach » vu bach, su sach, vu khach
van cau » van dau, van hau, van chat
mai hoi » mai khoi, dai hoi, lai hoi
cau luc » cau truc, cau phuc
luc va » duc va, tuc va, loc va

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: vu sach ky nang ((xa hoi) OR (mai hoi)). hieu van cau luc va ((hanh di) OR (hanh de)) cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang ((xa hoi) or (mai hoi)). hieu van cau luc va ((hanh di) OR (hanh de)) cua triet~".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((xa hoi) or (mai hoi)). hieu van cau luc va ((hanh di) OR (hanh de)) cua triet*.