Perhaps you should try some spelling variations:
nang doi » nang doc, hang doi, nang dong
nang noi » nang doc
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
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: tu sach ky lang 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: tu sach ky lang xa hoi. hieu va cac toc xa ((nang doi) OR (nang noi)) va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky lang xa hoi. hieu va cac toc xa ((nang doi) or (nang noi)) va triet*.