Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
hieu van » hieu va, thien van, lieu va
van chat » cao chat
hanh vai » hanh vi, hanh va, hanh tai
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
duc ban » duc van, dua ban, duc man
x hoi » xa hoi, o hoi, x ho

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 x hoi. hieu van chat ((duc ban) OR (duc tan)) hanh vai ((cua triet) OR (su triet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. hieu van chat ((duc ban) or (duc tan)) hanh vai ((cua triet) OR (su triet))~".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu van chat ((duc ban) or (duc tan)) hanh vai ((cua triet) OR (su triet))*.