Perhaps you should try some spelling variations:
doanh khoan » doanh khoa, doanh hoan, doanh nhan
thuc doanh » thuc hanh, thuc dan, chuc danh
khoan phai » khong phai, khoa phau, khoan hoi
phai tieng » phap tieng, phan tieng, pham tieng
sach tien » sach tren, sach thieu
tien thuc » trien thuc, kien thuc, bien thuc
thu sach » tu sach, thuat sach, thuoc sach
te sach » toc sach
tu cach » tu cac
cach tu » cach thuc
tu thu » tu tu, vu thu, tieu thu
nha he » nha ha, nha h2, nha xe
thong » trong

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 tien thuc doanh khoan phai tieng ) or ( tu cach tu thu sach nha he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach tien thuc doanh khoan phai tieng ) OR ( tu cach tu thu sach nha he thong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach tien thuc doanh khoan phai tieng ) or ( tu cach tu thu sach nha he thong ))*.