Perhaps you should try some spelling variations:
doanh dan » doanh ban, doanh van, doanh dao
tang van » dang van, hoang van, trong van
toc toan » ngoc toan, quoc toan, tich toan
dang xay » dang van, van xay
hieu van » hieu va, thien van, lieu va
dan cua » dan ca, ban cua, dai cua
cac toc » cac toi, cac nuoc, cac thoi
van cac » van hac, van cau, van bac
te sach » toc sach
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, lang van
cua te » cua tu

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