public function find($className, $id, $routing = null)
    {
        $type = $this->resolveTypeName($className);

        $params = [
            'index' => $this->getIndexName(),
            'type' => $type,
            'id' => $id,
        ];

        if ($routing) {
            $params['routing'] = $routing;
        }

        try {
            $result = $this->getClient()->get($params);
        } catch (Missing404Exception $e) {
            return null;
        }

        return $this->getConverter()->convertToDocument($result, $this);
    }