Jews usaly do not ask angels for help as per the RAMBAM. He writes (in Sanhedrin, Perek 11) in the fifth Yesod ha'Emunah the prohibition against serving Avodah Zarah -- that not only should a person not worship a Mal'ach, but he should also not make a Mal'ach a vehicle through which to reach Hashem. Yet in Sholom Alichem we ask the Angels we are addressing
בָּרְכוּנִי לְשָׁלוֹם מַלְאֲכֵי הַשָּׁלוֹם מַלְאָכֵי עֶלְיוֹן
so we ask angels to bless us with peace.