title: How to use gitlab search criteria
body: <p>In gitlab's doc, there is <a href="http://doc.gitlab.com/ee/api/projects.html#list-projects" rel="noreferrer">list projects API</a>,
  however I wonder how to use the <code>search</code> field.</p>
  
  <p>I've tried with <code>http://GITLAB_API/projects?search=QUERY&amp;private_token=xxx</code>, and it successfully returned projects those contain <code>QUERY</code> in their names, but I want to know if there is advanced search criteria available? For example, I want to get projects under certain namespace, is it possible to filter those projects through this api? Or any api else?</p>
  
  <p>Thank you!</p>