title: Unable to select some text from Google Docs with a simple regex
body: <p>I'm trying to highlight some text (in the example below I would like to highlight "ORGANIZA") with some regex on a Google Docs document, but I'm unable to make first work a simple regex to find the "category_name" string.</p>
  
  <p>Why this:</p>
  
  <pre><code>function highlightTextTwo() {
  
    /* DOCUMENT DEFINITION */
    var doc  = DocumentApp.openById('1M6JmJPndLS_hkdaUo5holsdxB5GSSrcWMa1j4Hh7Dig');
  
    /* VARIABLE DEFINITION */  
    var highlightStyle = {};
    var paras = doc.getParagraphs();
    var textLocation = {};
    var i;
  
    /* REGEX DEFINITION */  
    var MyRegex = new RegExp('category_name','i');    
  
    /* COLOR STYLE DEFINITION */
    highlightStyle[DocumentApp.Attribute.FOREGROUND_COLOR] = '#FF0000'; 
  
  
    /* CODE */  
    for (i=0; i&lt;paras.length; ++i) {
      Logger.log( paras[i].findText(MyRegex) );
    }
  
  
  }
  </code></pre>
  
  <p>applied to this document:</p>
  
  <pre><code>{
      "map_image": "mapa_con_close_button.png",
      "categories":[
          {
              "category_id": 1,
              "category_name": "ORGANIZA",
              "color": "#4591D0",
              "icon_image": "Organiza.png"
          },
          {
              "category_id": 2,
              "category_name": "DELEGA",
              "color": "#94C5DD",
              "icon_image": "Delega.png"
          },
          {
              "category_id": 3,
              "category_name": "NEGOCIA Y GESTIONA EL CONFLICTO",
              "color": "#E7344A",
              "icon_image": "Negocia_y_Gestiona.png"
          }
  </code></pre>
  
  <p>returns this:</p>
  
  <pre><code>[15-06-03 20:12:48:026 CEST] null
  [15-06-03 20:12:48:027 CEST] null
  [15-06-03 20:12:48:028 CEST] null
  [15-06-03 20:12:48:029 CEST] null
  [15-06-03 20:12:48:030 CEST] null
  [15-06-03 20:12:48:030 CEST] null
  </code></pre>
  
  <p>instead the some nulls and one "category_name".</p>