Perhaps you should try some spelling variations:
doanh khoa » toan khoa
tham thuoc » pham thuoc, tham thuc, nha thuoc
hoc thong » hoc thuong, hoc trong, hoc hong
sach tham » sach nha
khoan hoi » khoan nhoi, khoa hoi, khoa doi
hoi thong » hoi thuong, hoi trong, hoa thong
sanh tai » sang tai, hanh tai, anh tai
vu doanh » va doanh, su doanh, van doanh
khoa hoc » hoa hoc
toc sach » hoc sach, doc sach, thuoc sach
thuoc co » thuc co, thuoc bo, thuoc ho
co khoan » coc khoan, ho khoan, cac khoan
so sanh » do sanh
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 hoc thong ) or ( toc sach tham thuoc co khoan hoi thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sanh tai vu doanh khoa hoc thong ) OR ( toc sach tham thuoc co khoan hoi thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sanh tai vu doanh khoa hoc thong ) or ( toc sach tham thuoc co khoan hoi thong ))*.