Perhaps you should try some spelling variations:
doanh dao » doanh bao, doanh cao, doanh giao
hieu van » thien van, lieu va, hieu ve
thuc van » thuc vat, thuc dan, thuc va
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
tuc van » truc van, tuc va, duc van
dao cua » dai cua, day cua, dan cua
cua te » cua tu

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. ((hieu van) OR (hieu va)) cac ((tuc van) OR (thuc van)) doanh dao cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang xa hoi. ((hieu van) OR (hieu va)) cac ((tuc van) or (thuc van)) doanh dao cua te~".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. ((hieu van) OR (hieu va)) cac ((tuc van) or (thuc van)) doanh dao cua te*.