title: Android firebase apply multiple queries
body: <p>I have following database</p>
  
  <pre><code>-KYTfJZQbg0RVzHeecIS
       createdAt: 1481204648530
       message: "rgd"
       read: false
       reciever: "583d15cf45f3330807364c55"
       sender: "58490e9945f33364ac6cd7b1"
       updateAt: 1481204648654
  </code></pre>
  
  <p>Now I want to filter the result for "READ"==FALSE AND "SENDER"==58490e9945f33364ac6cd7b1</p>
  
  <p>how can I achieve this?</p>
  
  <p>Any help would be appreciated
  Thanks</p>
  
  <p>EDIT :-</p>
  
  <p>I am using this in android as</p>
  
  <pre><code>Query query = reference.orderByChild("read").equalTo(false)
                  .orderByChild("sender").equalTo(datum.getEmployer().getEmployerId());
  </code></pre>
  
  <p>it gave <code>java.lang.IllegalArgumentException: You can't combine multiple orderBy calls!</code></p>