Edit in JSFiddle

function FirstCtrl($scope) {
    console.log($scope);
}

function SecondCtrl($scope) {
    console.log($scope);
}

<div ng-app="">
  <input type="text" ng-model="data.message">
  <h1>{{ data.message }}</h1>

  <div ng-controller="FirstCtrl">
    <input type="text" ng-model="data.message">
    <h1>{{ data.message }}</h1>
  </div>

  <div ng-controller="SecondCtrl">
    <input type="text" ng-model="data.message">
    <h1>{{ data.message }}</h1>
  </div>
      
  <hr>
  <input type="text" ng-model="msg">
  <h1>{{ msg }}</h1>

  <div ng-controller="FirstCtrl">
    <input type="text" ng-model="msg">
    <h1>{{ msg }}</h1>
  </div>

  <div ng-controller="SecondCtrl">
    <input type="text" ng-model="msg">
    <h1>{{ msg }}</h1>
  </div>
</div>