Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh di » thanh doi, thanh de, thanh do
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
cao duc » dao duc, cao suc, giao duc
bao duc » dao duc, bao luc, giao duc
su sach » vu sach
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
so sach » so sanh, bo sach, co sach
di su » doi su, ki su, da su

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) or (so sach)) ky lang xa hoi. hieu van ((bao duc) OR (cao duc)) va thanh di su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ky lang xa hoi. hieu van ((bao duc) OR (cao duc)) va thanh di su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sach)) ky lang xa hoi. hieu van ((bao duc) OR (cao duc)) va thanh di su triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (so sach)) ky lang xa hoi. hieu van ((bao duc) OR (cao duc)) va thanh di su triet*.