Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh tai » thanh tai, hang tai, han tai
hieu ve » hieu va, hieu van
duc van » duc va, duc manh, duc phan
tai cua » thai cua, tai cuc, tri cua
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
co hoi » co hoc
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky nang ((co hoi) OR (co loi)). hieu ve cac ((duc van) or (duc tan)) hanh tai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang ((co hoi) OR (co loi)). hieu ve cac ((duc van) OR (duc tan)) hanh tai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang ((co hoi) OR (co loi)). hieu ve cac ((duc van) or (duc tan)) hanh tai cua triet".
• Adding a wildcard symbol may retrieve word variants: te sac ky nang ((co hoi) OR (co loi)). hieu ve cac ((duc van) or (duc tan)) hanh tai cua triet*.