title: elasticsearch query string format
body: <p>I am using </p>
  
  <pre><code>SearchBuilder.searchSource.query(query_string).buildAsBytes() 
  </code></pre>
  
  <p>to perform the query string on elasticsearch servers.</p>
  
  <p>The problem is that I dont know what is the correct format of query string. For instance, I want to find all documents with <code>country</code> field to be <code>US</code>, I can use the restful api of </p>
  
  <pre><code>http://my.elastic.search.server/foo/dummy/_search?q=country:US
  </code></pre>
  
  <p>to get what I need. But in terms of java api, I tried <code>country:US</code>, <code>q=country:US</code>, and <code>{\"country\":\"US\"}</code>, but each time I got back <code>SearchPhaseExecutionException</code>. </p>
  
  <p>ElasticSearch's documentation does not shed any lights on what could be the format of query string in this case, and I have exhausted Google results related to this topic. Can someone help me on this? Thanks!</p>