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.