Thanks for the reply.
We did that, however, my question was a bit different. We want to customize the default email, so we have used a custom email template we have developed, and it sends the recent 10 blog posts. However, we want it to send ONLY the posts which were published in the last week at the moment of sending the email, and NOT anything else. So we don't want to send the same blog post in 2 consequent newsletters. Is that possible? I think there should be a HubL function, module, or property for this, but I didn't find anything in the Reference.