Q:

How to fetch a specific package updates? 

I wan to update a specific package (biblatex-ieee) that I use.  I do not want to update my whole system (I need to maintain specific versions for some SWs).  How to retrieve the updates of that specific package without updating the whole system?     

A:

You just have to do
sudo apt-get install texlive-bibtex-extra

as this package contains the needed biblatex-ieee.*  files. 
Also from https://launchpad.net/ubuntu/bionic/+package/texlive-bibtex-extra :

This package includes the following CTAN packages:
  ...
biblatex-ieee
  ...

