I'm trying to backup a blog service that may soon be shut down. 

It has one main page
For example: blog.com (this is NOT the actuall url, but just an example)

it has many subdomains 
Example: someone.blog.com

Each post represents a node with a number
Example: someone.blog.com/node/2343536 

It also has and option to list previous posts like:
someone.blog.com/blogs/someone?from=7

I tried to copy everything, however some subdomains are copied, some are not
and some are copied just partially (some posts but not all). I played with the
settings a little bit, but it didn't help. 

How to copy everything (and I mean LITTERALLY everything) so it can be browsed
offline? 

I just don't need media like images/audio/video etc. Html's are most
important. 

I also don't need to save anything outside of this domain (no external sites)

I tried to copy just one blog and it worked well. The problem is how to copy
all the blogs on this service automatically without saving them individually.

Thank you.