diff --git a/docs/00-intro.md b/docs/00-intro.md
index bacf7ff..a4caa1e 100644
--- a/docs/00-intro.md
+++ b/docs/00-intro.md
@@ -4,7 +4,7 @@ Welcome to the official Ulmus documentation.
 
 ## Quick start
 
-Creating a simple user entity:
+Creating a simple user exemple entity:
 
 */app/entity/user.php*
 ```php
@@ -21,29 +21,19 @@ class User
 {
     use \Ulmus\EntityTrait;
     
-    /**
-    * @Id
-    */
+    #[Field\Id]
     public int $id;
     
-    /**
-    * @Field 
-    */
+    #[Field]
     public string $fullname;
     
-    /**
-    * @Field 
-    */
+    #[Field]
     public ? string $email;
     
-    /**
-    * @Field('name' => 'is_admin')
-    */
+    #[Field]
     public bool $isAdmin = false;
     
-    /**
-    * @DateTime 
-    */
+    #[Field\Datetime]
     public Datetime $birthday;
 }
 ```
diff --git a/src/EntityCollection.php b/src/EntityCollection.php
index 9d4d165..0a6179e 100644
--- a/src/EntityCollection.php
+++ b/src/EntityCollection.php
@@ -58,6 +58,26 @@ class EntityCollection extends \ArrayObject {
         return null;
     }
 
+    public function extract(Callable $callback) : self
+    {
+        $idx = 0;
+        $replace = [];
+        $collection = new static();
+
+        foreach($this as $key => $item) {
+            if ( $callback($item, $key, $idx++) ) {
+                $collection->append($item);
+            }
+            else {
+                $replace[] = $item;
+            }
+        }
+
+        $this->replaceWith($replace);
+
+        return $collection;
+    }
+
     public function iterate(Callable $callback) : self
     {
         foreach($this as $item) {
@@ -117,17 +137,17 @@ class EntityCollection extends \ArrayObject {
 
     public function searchAll(/* mixed*/ $values, string $field, bool $strict = true, bool $compareArray = false) : self
     {
-        $obj = new static();
+        $collection = new static();
 
         $values = is_array($values) && $compareArray ? [ $values ] : $values;
 
         foreach((array) $values as $value) {
             foreach ($this->search($value, $field, $strict) as $item) {
-                $obj->append($item);
+                $collection->append($item);
             }
         }
 
-        return $obj;
+        return $collection;
     }
 
     public function diffAll(/* mixed */ $values, string $field, bool $strict = true, bool $compareArray = false) : self