Perhaps you should try some spelling variations:
dang thuoc » dung thuoc
thuoc sinh » hoc sinh, thu sinh, thuoc sach
sanh dang » anh dang, sanh dan, anh dong
sinh khoa » sinh hoc, sinh hoat, anh khoa
thuc hang » thuc hanh, thu hang, phuc hang
hang khoa » dung khoa
so sanh » do sanh
khoa he » hoa he, khoa hoc, khong he
sanh xa » sach xa, canh xa, sanh ca
xa thuc » va thuc, xa phuc, a thuc

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 dang thuoc sinh khoa he thong ) or ( so sanh xa thuc hang khoa he thong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( so sanh dang thuoc sinh khoa he thong ) OR ( so sanh xa thuc hang khoa he thong )).
• Adding a wildcard symbol may retrieve word variants: (( so sanh dang thuoc sinh khoa he thong ) or ( so sanh xa thuc hang khoa he thong ))*.