code: function (selector) {
          var i, l, ret = [];
  
          for (i = 0, l = this.length; i < l; i++) {
            DomQuery.find(selector, this[i], ret);
          }
  
          return DomQuery(ret);
        }
docs: Finds elements by the specified selector for each element in set.
  
  @method find
  @param {String} selector Selector to find elements by.
  @return {tinymce.dom.DomQuery} Set with matches elements.