Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
hieu va » lieu va, hieu qua
sac ky » cac ky, sai ky
cac so » cac co, cac bo, cac 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) or (sac ky)) nang x hoi. hieu va cac so ((van hanh) OR (van thanh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sac ky)) nang x hoi. hieu va cac so ((van hanh) OR (van thanh)) vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sac ky)) nang x hoi. hieu va cac so ((van hanh) OR (van thanh)) vi cua triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sac ky)) nang x hoi. hieu va cac so ((van hanh) OR (van thanh)) vi cua triet*.