Perhaps you should try some spelling variations:
doanh tang » doanh sang, doanh tong, doanh thanh
tang cua » mang cua, hang cua, tang luan
sach thu » sach thue, sach thieu, sach tham
va doanh » van doanh, vay doanh, va danh
sach tru » sach truc, sach tu, sach tren
cai luc » cau luc, dai luoc
nang xa » lang xa, nang ma, mang xa
qua cai » qua hai, qua cac, qua ca
luc va » duc va, tuc va, loc va
cua te » cua tu

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 tru) or (sach thu)) ((nang xa) OR (nang x)) hoi. hieu qua cai luc va doanh tang cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach tru) OR (sach thu)) ((nang xa) OR (nang x)) hoi. hieu qua cai luc va doanh tang cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach tru) or (sach thu)) ((nang xa) OR (nang x)) hoi. hieu qua cai luc va doanh tang cua te".
• Adding a wildcard symbol may retrieve word variants: toc ((sach tru) or (sach thu)) ((nang xa) OR (nang x)) hoi. hieu qua cai luc va doanh tang cua te*.