Perhaps you should try some spelling variations:
ve triet » va trien, su triet
nam thuc » nam thuoc, am thuc, nam thu
van hanh » van thanh, ban hanh, van anh
sach tu » sach thu, cach tu, sach uu
xang ma » tang ma, nang ma, sang ma
sach ty » sach y, sach thu, xach tay
hieu ve » hieu va, hieu van
ma hoi » mai hoi, xa hoi, ma hoa
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) OR (sach tu)) xang ma hoi. hieu ve ((nam thuc) or (cam xuc)) van hanh vi ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach tu)) xang ma hoi. hieu ve ((nam thuc) OR (cam xuc)) van hanh vi ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach tu)) xang ma hoi. hieu ve ((nam thuc) or (cam xuc)) van hanh vi ve triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach tu)) xang ma hoi. hieu ve ((nam thuc) or (cam xuc)) van hanh vi ve triet*.