Twitter – Does Twitter offer a “Tweet box api” that can be installed on any blogs and used by Twitter users

This seems to be your best bet for now within Google Search as Google may have added it as a special reserved word in a similar format to say c++

site:twitter.com inurl:status google+

The following seems to search Google and Google+ but if you look at the results in realtime, there are also results that do not make any sense.

twitter.com/?q=google%2B#!/search

It's not going through your firewall when it talks to the Twitter servers. Brizzly retrieves content from the Twitter API through its own connection and then stores it on their server and presents it to you while you're logged in. (It only does this when you're using it, though, otherwise you'd end up using all of your Twitter API limit.)

If your company doesn't allow usage of Twitter during the work day, I wouldn't recommend using Brizzly to get around it. Also, they may eventually figure it out and block it and similar sites, such as Hootsuite.