'求人募集中' is often used in Japanese. '求人募集していますか?'is the asking way of example.

Are you hiring right now? 今、バイト募集していますか？ or 今、求人を募集していますか？ ^.^

I think it depends on what kind of job you'd like to apply for, like just a grocery store such as Giant or Walmart, you can say like アルバイトの募集はしていますか？Which means that you'd like to work as a part-timer/casual worker, but not バイトの募集 since you are old enough to know how to act in public. 職員/従業員の募集はしていますか？In this case, you'd like to work there as a full-timer. However, it sounds like you made an unannounced visit to there and ask that kind of thing. So if people see an advertisement on a wall, usually they say,すみません、店舗の張り紙を見たのですが、まだ募集は行ってますか? but normally in Japan, people call a place to make an appointment for an interview.

今、職員の募集はしていますか？for full-time worker, but if it's a part-timer/casual worker, 今、アルバイトの募集はしていますか？Using ’バイト' is not appropriate if you REALLY want to get a job.