Perhaps you should try some spelling variations:
doanh van » doan van, doanh va, doanh ban
cau tren » cu tren, dau tren, ca tren
thuc dan » thuc hanh, hoc dan, thuc vat
danh vai » danh sai, danh va, dang van
tai thuc » thai thuc, tri thuc, dai thuc
trang va » tran van, hang va
ke trang » ke toan
hieu ve » hieu va, hieu van
sach ke » sach kem, sach de, sach che
tu sach » thu sach, su sach, te sach
ve tai » te tai, de tai, le tai
va hoi » xa hoi, va hoc, va hoa

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: tu sach ke trang va hoi. hieu ve tai thuc dan ((danh vai) OR (doanh van)) cau tren~.
• Adding a wildcard symbol may retrieve word variants: tu sach ke trang va hoi. hieu ve tai thuc dan ((danh vai) or (doanh van)) cau tren*.