Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
danh sai » dung sai, danh bat, danh dau
nam danh » nam dinh, nam dan
thu nam » tu nam, thu nhap, thu nhat
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ma hoi » xa hoi, ma hoa, me hoi
ve nam » he nam, va nam, le nam

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 ky nang ((ma hoi) or (mai hoi)). hieu ve nam thu nam danh sai ((cua triet) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((ma hoi) OR (mai hoi)). hieu ve nam thu nam danh sai ((cua triet) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang ((ma hoi) or (mai hoi)). hieu ve nam thu nam danh sai ((cua triet) or (va triet))*.