public function scopeFilterBySurveyAndCategory(Builder $query, ?string $selected_category, ?string $selected_survey): Builder 	{ 		return $query->whereHas('parent', function ($query) use ($selected_survey, $selected_category) { 			$query->when(isset($selected_survey), function ($query) use ($selected_survey, $selected_category) { 				$query->whereHas('category', function ($query) use ($selected_survey, $selected_category) { 					$query->where('survey_id', $selected_survey)->when(isset($selected_category), function ($query) use ($selected_category) { 						$query->where('id', $selected_category); 					}); 				}); 			}); 		}); 	}