Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
nang noi » nang doc
nang doi » nang doc, hang doi, nang dong
te sach » toc sach
hieu va » lieu va, hieu qua
ky tang » ky nang, ky dang, kho tang
ky lang » ky nang, ky dang, tay lang
cac toc » cac toi, cac nuoc, cac thoi
toc xa » tuc xa, toc ta, hoc xa

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

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