private function query_products( $args ) {

		// Set base query arguments
		$query_args = array(
			'fields'      => 'ids',
			'post_type'   => 'product',
			'post_status' => 'publish',
			'meta_query'  => array(),
		);

		if ( ! empty( $args['type'] ) ) {

			$types = explode( ',', $args['type'] );

			$query_args['tax_query'] = array(
				array(
					'taxonomy' => 'product_type',
					'field'    => 'slug',
					'terms'    => $types,
				),
			);

			unset( $args['type'] );
		}

		// Filter products by category
		if ( ! empty( $args['category'] ) ) {
			$query_args['product_cat'] = $args['category'];
		}

		// Filter by specific sku
		if ( ! empty( $args['sku'] ) ) {
			if ( ! is_array( $query_args['meta_query'] ) ) {
				$query_args['meta_query'] = array();
			}

			$query_args['meta_query'][] = array(
				'key'     => '_sku',
				'value'   => $args['sku'],
				'compare' => '=',
			);

			$query_args['post_type'] = array( 'product', 'product_variation' );
		}

		$query_args = $this->merge_query_args( $query_args, $args );

		return new WP_Query( $query_args );
	}