diff --git a/src/Searcher/MongoSearcher.php b/src/Searcher/MongoSearcher.php
index da515080e..e5bcd9a30 100644
--- a/src/Searcher/MongoSearcher.php
+++ b/src/Searcher/MongoSearcher.php
@@ -222,7 +222,7 @@ public function delete($id): void
 
     public function truncate()
     {
-        $this->_collection->drop();
+        $this->_collection->remove();
 
         return $this;
     }
@@ -276,7 +276,7 @@ public function getAllWatches(): array
 
     public function truncateWatches()
     {
-        $this->_watches->drop();
+        $this->_watches->remove();
 
         return $this;
     }
diff --git a/tests/LazyContainerProperties.php b/tests/LazyContainerProperties.php
index f449ba2d8..d0996077d 100644
--- a/tests/LazyContainerProperties.php
+++ b/tests/LazyContainerProperties.php
@@ -3,6 +3,7 @@
 namespace XHGui\Test;
 
 use LazyProperty\LazyPropertiesTrait;
+use MongoDB;
 use Slim\Slim as App;
 use Slim\View;
 use XHGui\Controller\ImportController;
@@ -24,6 +25,8 @@ trait LazyContainerProperties
     protected $import;
     /** @var MongoSearcher */
     private $mongo;
+    /** @var MongoDB */
+    protected $mongodb;
     /** @var RunController */
     protected $runs;
     /** @var App */
@@ -44,6 +47,7 @@ protected function setupProperties(): void
             'app',
             'import',
             'mongo',
+            'mongodb',
             'runs',
             'saver',
             'searcher',
@@ -90,6 +94,11 @@ protected function getMongo()
         return $this->di['searcher.mongodb'];
     }
 
+    protected function getMongoDb()
+    {
+        return $this->di[MongoDB::class];
+    }
+
     protected function getSearcher()
     {
         return $this->di['searcher'];
diff --git a/tests/Searcher/MongoHelper.php b/tests/Searcher/MongoHelper.php
new file mode 100644
index 000000000..776e97d20
--- /dev/null
+++ b/tests/Searcher/MongoHelper.php
@@ -0,0 +1,53 @@
+<?php
+
+namespace XHGui\Test\Searcher;
+
+use ArrayIterator;
+use MongoDB;
+use MultipleIterator;
+
+class MongoHelper
+{
+    /** @var MongoDB */
+    private $mongodb;
+    /** @var array */
+    private $indexes = [];
+
+    public function __construct(MongoDB $mongodb)
+    {
+        $this->mongodb = $mongodb;
+    }
+
+    public function dropCollection(string $collectionName): void
+    {
+        $collection = $this->mongodb->selectCollection($collectionName);
+        $collection->drop();
+    }
+
+    public function createCollection(string $collectionName, array $indexes): void
+    {
+        $collection = $this->mongodb->createCollection($collectionName);
+
+        foreach ($indexes as [$keys, $options]) {
+            $collection->createIndex($keys, $options);
+        }
+        $this->indexes[$collectionName] = $indexes;
+    }
+
+    public function getIndexes(string $collectionName): MultipleIterator
+    {
+        $collection = $this->mongodb->selectCollection($collectionName);
+        $expectedIndexes = $this->indexes[$collectionName];
+
+        $resultIndexInfo = $collection->getIndexInfo();
+        $resultIndexes = array_column($resultIndexInfo, 'key');
+        $resultIndexNames = array_column($resultIndexInfo, 'name');
+
+        $iterator = new MultipleIterator();
+        $iterator->attachIterator(new ArrayIterator($resultIndexes));
+        $iterator->attachIterator(new ArrayIterator($resultIndexNames));
+        $iterator->attachIterator(new ArrayIterator($expectedIndexes));
+
+        return $iterator;
+    }
+}
diff --git a/tests/Searcher/MongoTest.php b/tests/Searcher/MongoTest.php
index aee07c053..d7f772e3f 100644
--- a/tests/Searcher/MongoTest.php
+++ b/tests/Searcher/MongoTest.php
@@ -183,4 +183,83 @@ public function testSaveRemove(): void
         $this->assertTrue($this->mongo->saveWatch($result[0]));
         $this->assertCount(0, $this->mongo->getAllWatches());
     }
+
+    public function testTruncateResultsPreserveIndexes(): void
+    {
+        $helper = new MongoHelper($this->mongodb);
+
+        // dropping "results" collection using raw client
+        // (indexes are lost)
+        $helper->dropCollection('results');
+
+        // recreating collection "results" with indexes
+        $expectedIndexes = [
+            [['_id' => 1], ['name' => '_id_']],
+            [['meta.SERVER.REQUEST_TIME' => -1], ['name' => 'meta_srv_req_t']],
+            [['profile.main().wt' => -1], ['name' => 'profile_wt']],
+            [['profile.main().mu' => -1], ['name' => 'profile_mu']],
+            [['profile.main().cpu' => -1], ['name' => 'profile_cpu']],
+            [['meta.url' => 1], ['name' => 'meta_url']],
+            [['meta.simple_url' => 1], ['name' => 'simple_url']],
+            [['meta.request_ts' => 1], ['name' => 'req_ts', 'expireAfterSeconds' => 432000]],
+        ];
+        $helper->createCollection('results', $expectedIndexes);
+
+        $this->importFixture($this->saver);
+
+        $result = $this->mongo->getAll(new SearchOptions());
+        $this->assertCount(7, $result['results']);
+
+        $this->mongo->truncate();
+
+        $result = $this->mongo->getAll(new SearchOptions());
+        $this->assertEmpty($result['results']);
+
+        // assert that all indexes are intact after truncating
+        // compare result against expected indexes
+        foreach ($helper->getIndexes('results') as [$index, $name, $expectedIndex]) {
+            $this->assertEquals($expectedIndex[0], $index);
+
+            $expectedName = $expectedIndex[1]['name'];
+            $this->assertEquals($expectedName, $name);
+
+            if ($name === 'meta.request_ts') {
+                $this->assertArrayHasKey('expireAfterSeconds', $expectedIndex[1]);
+                $this->assertEquals(432000, $expectedIndex[1]['expireAfterSeconds']);
+            }
+        }
+    }
+
+    public function testTruncateWatchesPreserveIndexes(): void
+    {
+        $helper = new MongoHelper($this->mongodb);
+
+        // dropping "watches" collection using raw client
+        // (indexes are lost)
+        $helper->dropCollection('watches');
+
+        // recreating collection "watches" with indexes
+        $expectedIndexes = [
+            [['_id' => 1], ['name' => '_id_']],
+            [['name' => -1], ['name' => 'test_name']],
+        ];
+        $helper->createCollection('watches', $expectedIndexes);
+
+        $this->searcher->saveWatch(['name' => 'strlen']);
+
+        $result = $this->searcher->getAllWatches();
+        $this->assertCount(1, $result);
+
+        $this->mongo->truncateWatches();
+
+        $result = $this->searcher->getAllWatches();
+        $this->assertEmpty($result);
+
+        // compare result against expected indexes
+        foreach ($helper->getIndexes('watches') as [$index, $name, $expectedIndex]) {
+            $this->assertEquals($expectedIndex[0], $index);
+            $expectedName = $expectedIndex[1]['name'];
+            $this->assertEquals($expectedName, $name);
+        }
+    }
 }