Perhaps you should try some spelling variations:
doanh qua » doanh quan, danh qua, doanh quang
doanh cua » doanh luan
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
lang van » dang van, tang van, hoang van
te sach » toc sach
lang xa » lang ha, dang xay
cua tre » cua te, cuu tre, cua triet

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