Question

Why is anti viral medicines harder than making anti bacterial medicines

Answer 1

its because virus dont have their machinery of own.
When they enter into our body, they use our cells as their machinery.
So, to kill viruses we've to kill some of our cells as well.Hence, making anti-viral drugs is more difficult than making anti-bacterial drugs.

Answer 2

The same reason why we arent able to cure AIDS but are able to do it with other bacterial infections.
Since viruses do not use biochemical pathways as bacteria do.They have their unique independent mechanisms.

Cheers!