Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
hieu van » hieu va, thien van, lieu va
nang noi » nang doc
nang doi » nang doc, hang doi, nang dong
tu sach » thu sach, su sach, te sach
van cac » van hac, van cau, van bac
ky dang » ky nang, ky danh
ky tang » ky nang, kho tang, ky trong
cac tac » cac toc, cac bac, cac dac
tac xa » tuc xa, tac da

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ky tang) OR (ky dang)) xa hoi. hieu van cac tac xa ((nang doi) or (nang noi)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky tang) OR (ky dang)) xa hoi. hieu van cac tac xa ((nang doi) OR (nang noi)) va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky tang) OR (ky dang)) xa hoi. hieu van cac tac xa ((nang doi) or (nang noi)) va triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky tang) OR (ky dang)) xa hoi. hieu van cac tac xa ((nang doi) or (nang noi)) va triet*.