问jQuery -获取父div的好友div中的元素

EN

<div class="container-fluid">
  <div class="input-page">...</div>
  <!-- field 1 -->
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding">...</div>
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding">...</div>
  <!-- field 2 -->
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding">...</div>
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding">...</div>
  <!-- field 3 -->
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding"> <!-- I want to grab this block -->
    <div class="x_panel">
      <div class="x_content">
        <form class="data-table">
          <div class="row">...</div>
          <div class="row">...</div>
  <div class="col-md-12 col-sm-12 col-xs-12 no-padding">
    <div class="btn-group">
      <button>Add</button> <!-- when I click this button -->
      <button>Other</button>
    </div>
  </div>
</div>