So, making your Google+ posts available for viewing only to people in your circles isn't enough. Maybe you routinely post risque stuff you don't want minors to see, or things you'd rather share only with your countrymen. It doesn't matter what your reason is for wanting tighter restrictions -- what matters is that you can now do so, thanks to the latest Google+ update. All you need to do is go to Profile Settings and find a new section called Audience. Within that section, you can put an age limit (say, make your posts available to people older than 18 or 21 only) on your content or show it only to folks from select countries. You can even set different age restrictions for each country, if you want to be extra thorough, whether you have a personal profile or run a business page. Couple this with an update from July that lets you use almost any name you want on the social network, and Google+ is looking mighty customizable these days.