Update README.md. Adding via Query example

Author: rodrigotroche

README.md

@@ -185,6 +185,23 @@ class PostController extends Controller
 }
 ```
 
+## Adding via Query
+The `searchable()` method will chunk the results of the query and add the records to your search index. 
+
+$post = Post::find(1);
+
+// You may also add record via collection...
+$post->searchable();
+
+// OR
+
+$posts = Post::where('year', '>', '2018')->get();
+
+// You may also add records via collections...
+$posts->searchable();
+
+When using constraints apply it after the constraints are added to the query, as seen in the above example.
+
 ## OrderBy
 An `orderBy()` statement can now be applied to the search query similar to the `where()` statement.