Q: I need to retrieve deleted text messages from iCloud for a iPhone 4S. How can I do this?

If they messages were on your phone when you backed it up, you should be able to restore it by restoring to the entire backup. 

Restoring to an iCloud backup has to be done in the initial setup process.  If you have any data on your phone now that is not in the backup that you want to save you'll need to do that first.  Then go to Settings>General>Reset and tap Erase All Content and Settings.  You will then go through the setup screens as you did when the phone was new. When given the option, choose Restore from iCloud Backup (see image below).  Be sure you are connected to wifi and your charger as this will take some time to finish.