Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
hieu ve » hieu van
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
bac so » bac son, bac si, bac ho
vi cua » vai cua, di cua
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y nang x hoi. ((hieu ve) or (hieu va)) ((bac so) OR (bac bo)) van hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang x hoi. ((hieu ve) OR (hieu va)) ((bac so) OR (bac bo)) van hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang x hoi. ((hieu ve) or (hieu va)) ((bac so) OR (bac bo)) van hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x hoi. ((hieu ve) or (hieu va)) ((bac so) OR (bac bo)) van hanh vi cua triet*.