Perhaps you should try some spelling variations:
cua triet » su triet, va triet
van hanh » van thanh, ban hanh, van anh
cua viet » ca viet, hoa viet, cua vat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ve bac » ve cac, ve ban, he bac
ve bao » te bao, va bao
bo van » vo van, so van, do van
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: tu sach ky nang x hoi. hieu ((ve bac) OR (ve bao)) bo van hanh vi ((cua triet) OR (cua viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. hieu ((ve bac) or (ve bao)) bo van hanh vi ((cua triet) OR (cua viet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu ((ve bac) or (ve bao)) bo van hanh vi ((cua triet) OR (cua viet))*.