For most purposes, the “Non-paid Search Traffic” Advanced Segment predefined in Google Analytics is too broad to be very useful.
A significant portion of organic traffic to most websites results from branded searches. For example, if you work at a company named Get to the Point that makes pencil sharpeners, you should not treat organic traffic originating from “get to the point” or “gettothepoint.com” searches the same as organic traffic originating from “pencil sharpener” searches.
You should instead define your own Advanced Segment to exclude company name, domain name, and possibly branded product names as well. A regular expression, as shown in the screen shot, can help to exclude multiple variations.
You might also specify that the segment exclude (not provided), which is the keyword that the Google search engine passes through to Google Analytics for searchers who were logged into gmail/Google; in many instances, the obscured keyword is also branded.
In applying this segment to your visitor and conversion reports, you’ll be sure to gauge your actual organic performance much more accurately.