Google Plus gets another feature update today. You can now search for keywords based on location.
It would search for posts accessible to you which have location data shared by the poster.
You get the option to filter the results by city and even by zip code. Google developer Alex Unger spoke about this functionality:
Today, we are introducing a new feature that lets you filter Google+ search results by location. On a search results page, select the “From Everywhere” menu, and enter the city or zip code you’re interested in. This way, you can view sunsets from Maui, football in Green Bay, or traffic in London. For posts to appear in location-filtered search results, users must have explicitly added a location to their post, either from desktop or mobile.