how to display select2 after user input 3 data

I have select2 here to display user email data, but data can be up to tens of thousands, and that makes my select2 very slow, is there a method to only display after 3-letter user input?

this my script select2

$('#add_form').find("#list_user").select2({
                              width: "100%",
                              placeholder: "Choose User by Email...",
                              ajax: {
                                url: "{{ route('getuser') }}",
                                dataType: "json",
                                delay: 250,
                                processResults: function(data) {
                                  return {
                                    results: $.map(data, function(obj) {
                                      return {
                                        id: obj.email,
                                        text: obj.email
                                      };
                                    })
                                  };
                                },
                              }
                            });

and this my controller

public function getUser(Request $request)
        {
            $search = $request->input('term', '');
            $user = DB::table('users.users')->where('email','LIKE','%'.$search.'%')
                    ->get();
            return response()->json($user);
        }