Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
hieu ve » hieu va, hieu van
vai cua » dai cua, hai cua, lai cua
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
cac so » cac co, cac bo, cac ho
so van » su van, vo van
x hoi » o hoi, x ho, 5 hoi

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) OR (xa hoi)). hieu ve cac so van hanh vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sac ky)) nang ((x hoi) OR (xa hoi)). hieu ve cac so van hanh vai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sac ky)) nang ((x hoi) OR (xa hoi)). hieu ve cac so van hanh vai cua triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sac ky)) nang ((x hoi) OR (xa hoi)). hieu ve cac so van hanh vai cua triet*.