Search engines tailor (personalise) search results based on previous search activities, sites visited, social media activity and user location.

Previous search activities are monitored through the use of signed-in user accounts and tracking cookies.  These tracking cookies are used to keep track of activity when the user is not logged in.

Social media activity is monitored by social sites (i.e. Google Plus in particular) and Plus Ones and/or Likes are used to determine the users' response search results returned to the user.

The users IP address gives and indication of the users location when performing the search. For example a search for restaurants usually returns restaurants in the location of the user.

The only ways to retrieve 'raw' search results (or unbiased search ranking) are to

1. Log in on a proxy server after clearing all cookies and logging out of all accounts or 
2. Use Google Adwords - Ad Preview and Diagnosis or 
3. Use SEO tools that communicate directly through the Google API