Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
hang van » hoang van, dang van, tang van
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
van cau » van dau, van hau, van chat
cau duc » cao duc, cau luc, chu duc
y nang » ky nang, ly nang, v nang
ma hoi » xa hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang ((ma hoi) OR (mai hoi)). hieu van cau duc anh ((hang van) or (hang va)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((ma hoi) OR (mai hoi)). hieu van cau duc anh ((hang van) OR (hang va)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ((ma hoi) OR (mai hoi)). hieu van cau duc anh ((hang van) or (hang va)) cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((ma hoi) OR (mai hoi)). hieu van cau duc anh ((hang van) or (hang va)) cua triet*.