Perhaps you should try some spelling variations:
van doanh » toan doanh, van dong, van thanh
toc sach » doc sach, thuoc sach, nuoc sach
doanh va » doan va, doanh tai, doanh cua
hoc sach » hoc sinh, hoc cac, hoc anh
thu bang » thu ban, thu hang, chu bang
suc van » su van, duc van, luc van
cao suc » cao su, cao duc
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va
bang xa » lang xa, bang va, mang xa
va cuu » va cau, va chu, va huu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) OR (hoc sach)) thu bang xa hoi. ((hieu va) or (hieu qua)) cao suc van doanh va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) thu bang xa hoi. ((hieu va) OR (hieu qua)) cao suc van doanh va cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) thu bang xa hoi. ((hieu va) or (hieu qua)) cao suc van doanh va cuu tre*".