Zoho Campaigns - Creating a flow based on the user replying to us.

Zoho Campaigns - Creating a flow based on the user replying to us.

Hello dear community,

Hope all is fine for your nowadays. 

We would like to create what seems to be a pretty simple campaign that would go as follow. 

Target : 100 prospects. 
Flow : 

Send email 1 to 100 prospects. 
Send email 2 to only those who did not reply - 4 days after email 1 
Send email 3 to only those who did not reply - 5 days after email 2 

Talking with the support, it seems that it is not feasible within Zoho Campaigns. 

How would you guys do to achieve such an easy thing ? I have seen some topics about a "reply-to" feature. Is it the way to go ? 

Best from Paris, 

Alexandre