Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
nang doc » nang luc
hieu van » hieu va, thien van, lieu va
nang doi » nang noi, hang doi, nang dong
cac toc » cac toi, cac nuoc, cac thoi
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cac tuc » cac tu, cac tac, cac nuoc
ky hang » ky nang, ly hang, ky dang
va hoa » van hoa, va hoc, ma hoa

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 hang va hoa. hieu van ((cac tuc) or (cac toc)) xa ((nang doi) OR (nang doc)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky hang va hoa. hieu van ((cac tuc) OR (cac toc)) xa ((nang doi) OR (nang doc)) cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky hang va hoa. hieu van ((cac tuc) or (cac toc)) xa ((nang doi) OR (nang doc)) cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky hang va hoa. hieu van ((cac tuc) or (cac toc)) xa ((nang doi) OR (nang doc)) cua viet*.