Perhaps you should try some spelling variations:
vat doanh » van doanh, vay doanh, va doanh
hieu van » hieu va, thien van, lieu va
dang xay » dang van, van xay
bac thuc » bao thuc, bac thua, cach thuc
van bac » van ban, van bao, van hac
va chua » vua chua, ca chua, va chu
te sach » toc sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va cua » via cua, ca cua, ma cua

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 ((nang xa) or (dang xay)) hoi. hieu van bac thuc vat doanh ((va cua) OR (va chua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang xa) OR (dang xay)) hoi. hieu van bac thuc vat doanh ((va cua) OR (va chua)) te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang xa) or (dang xay)) hoi. hieu van bac thuc vat doanh ((va cua) OR (va chua)) te*".