Perhaps you should try some spelling variations:
ve triet » va trien, su triet
van hanh » van thanh, ban hanh, van anh
cam tuc » cam tu, nam thuc, dam thuc
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
ty tang » tay tang, ty xang, ty hang
hieu ve » hieu va, hieu van
ma hoi » mai hoi, ma hoa, me hoi
vi ve » va ve, gi ve, ve ve

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 ty tang ((ma hoi) or (xa hoi)). hieu ve ((cam tuc) or (cam xuc)) van hanh vi ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty tang ((ma hoi) OR (xa hoi)). hieu ve ((cam tuc) OR (cam xuc)) van hanh vi ve triet.
• Adding a wildcard symbol may retrieve word variants: su sach ty tang ((ma hoi) or (xa hoi)). hieu ve ((cam tuc) or (cam xuc)) van hanh vi ve triet*.