Perhaps you should try some spelling variations:
tao khoang » tao zhang
doanh khoa » toan khoa
khoang pho » khoang thoi, hoang phe, khoang thi
bai thuoc » ban thuoc, bai hoc, cay thuoc
thuoc tao » thuoc tai, thuoc tan, thuoc bao
sanh tai » sang tai, hanh tai, anh tai
vu doanh » va doanh, su doanh, van doanh
sach bai » sach dao, cac bai, sach xa
so sanh » do sanh
khoa he » hoa he, khoa hoc, khong he
te sach » toc sach
tai vu » tai tu, thi vu, hai vu

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( so sanh tai vu doanh khoa he thong ) or ( te sach bai thuoc tao khoang pho thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sanh tai vu doanh khoa he thong ) OR ( te sach bai thuoc tao khoang pho thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sanh tai vu doanh khoa he thong ) or ( te sach bai thuoc tao khoang pho thong ))*.