Perhaps you should try some spelling variations:
chat triet » chet triet, phat trien, chat thien
van thanh » ban thanh, van tuan
thanh lam » thanh lap, hanh lam, thanh nam
hieu van » hieu va, thien van, lieu va
lam chat » luan chat, cao chat, ly chat
van cau » van dau, van hau, van chat
cau duc » cao duc, cau luc, chu duc
duc van » duc va, duc tan, duc manh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
o hoi » co hoi, o hoc, o hoa
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky nang ((o hoi) or (o hai)). hieu van cau duc van thanh lam chat triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ((o hoi) OR (o hai)). hieu van cau duc van thanh lam chat triet.
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ((o hoi) or (o hai)). hieu van cau duc van thanh lam chat triet*.