diff --git a/core/modules/search/lib/Drupal/search/Controller/SearchController.php b/core/modules/search/lib/Drupal/search/Controller/SearchController.php
index 32a5c54..9966c52 100644
--- a/core/modules/search/lib/Drupal/search/Controller/SearchController.php
+++ b/core/modules/search/lib/Drupal/search/Controller/SearchController.php
@@ -69,8 +69,7 @@ public function view(Request $request, SearchPageInterface $entity, $keys = '')
 
     $plugin = $entity->getPlugin();
     $plugin->setSearch($keys, $request->query->all(), $request->attributes->all());
-    // Default results output is an empty string.
-    $results = array('#markup' => '');
+    $results = array();
 
     // Process the search form. Note that if there is
     // \Drupal::request()->request data, search_form_submit() will cause a
@@ -89,9 +88,11 @@ public function view(Request $request, SearchPageInterface $entity, $keys = '')
     }
     // The form may be altered based on whether the search was run.
     $build['search_form'] = $this->entityManager()->getForm($entity, 'search');
-    $build['search_results_title'] = array(
-      '#markup' => '<h2>' . $this->t('Search Results') . '</h2>',
-    );
+    if (count($results)) {
+      $build['search_results_title'] = array(
+        '#markup' => '<h2>' . $this->t('Search results') . '</h2>',
+      );
+    }
 
     $build['search_results'] = array(
       '#theme' => array('item_list__search_results__' . $plugin->getPluginId(), 'item_list__search_results'),
@@ -104,7 +105,7 @@ public function view(Request $request, SearchPageInterface $entity, $keys = '')
       '#attributes' => array(
         'class' => array(
           'search-results',
-          $plugin->getPluginId() . '_search-results',
+          $plugin->getPluginId() . '-results',
         ),
       ),
     );
diff --git a/core/modules/search/lib/Drupal/search/Plugin/SearchInterface.php b/core/modules/search/lib/Drupal/search/Plugin/SearchInterface.php
index 8aeb0ce..2ff0ad7 100644
--- a/core/modules/search/lib/Drupal/search/Plugin/SearchInterface.php
+++ b/core/modules/search/lib/Drupal/search/Plugin/SearchInterface.php
@@ -75,7 +75,9 @@ public function execute();
    * Executes the search and builds render arrays for the result items.
    *
    * @return array
-   *   An array of search_result render arrays.
+   *   An array of render arrays of search result items (generally each item
+   *   has '#theme' set to 'search_result'), or an empty array if there are no
+   *   results.
    */
   public function buildResults();
 
diff --git a/core/modules/search/lib/Drupal/search/Tests/SearchPreprocessLangcodeTest.php b/core/modules/search/lib/Drupal/search/Tests/SearchPreprocessLangcodeTest.php
index 079e57c..13f5a8d 100644
--- a/core/modules/search/lib/Drupal/search/Tests/SearchPreprocessLangcodeTest.php
+++ b/core/modules/search/lib/Drupal/search/Tests/SearchPreprocessLangcodeTest.php
@@ -87,7 +87,7 @@ function testPreprocessStemming() {
     $this->drupalPostForm('search/node', $edit, t('Advanced search'));
 
     // Check if the node has been found.
-    $this->assertText('Search Results');
+    $this->assertText('Search results');
     $this->assertText('we are testing');
 
     // Search for the same node using a different query.
@@ -95,7 +95,7 @@ function testPreprocessStemming() {
     $this->drupalPostForm('search/node', $edit, t('Advanced search'));
 
     // Check if the node has been found.
-    $this->assertText('Search Results');
+    $this->assertText('Search results');
     $this->assertText('we are testing');
   }
 }