Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
van doan » van doanh, van toan, van hoan
sach ty » sach y, sach tu, sach thu
va doan » va doanh, va dan, va don
cac tuc » cac toc, cac tu, cac tac
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu van
ty nang » ky nang, ty xang, ty hang
hieu va » lieu va, hieu qua
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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 ty nang ma hoi. ((hieu ve) or (hieu va)) cac tuc ((va doan) or (van doan)) vi cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ma hoi. ((hieu ve) OR (hieu va)) cac tuc ((va doan) OR (van doan)) vi cua viet.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ma hoi. ((hieu ve) or (hieu va)) cac tuc ((va doan) or (van doan)) vi cua viet*.