Perhaps you should try some spelling variations:
van doanh » toan doanh, van dong, van thanh
te sach » toc sach
cua cua » cua chua, qua cua, cua cha
tuc van » thuc van, truc van, tuc va
cac tuc » cac toc, cac tu, cac tac
hieu va » lieu va, hieu qua
sach v » sach va, sach y, sach 2
me hoi » le hoi
v nang » va nang, vu nang, van nang
ca cua » co 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 v nang ((me hoi) or (ma hoa)). hieu va cac tuc van doanh ((cua cua) OR (ca cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v nang ((me hoi) OR (ma hoa)). hieu va cac tuc van doanh ((cua cua) OR (ca cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v nang ((me hoi) or (ma hoa)). hieu va cac tuc van doanh ((cua cua) OR (ca cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach v nang ((me hoi) or (ma hoa)). hieu va cac tuc van doanh ((cua cua) OR (ca cua)) tre*.