We use הסברה in a more propaganda related way. The act of explaining in purpose ti convince someone.
A timid explanation is הסבר.
Do you know how the verb form for "הסבר" would differ from that for "הסברה"?
It is interesting to note that the feminine form is the one that went into Yiddish, pronounced hazBORe (with the usual shift of the accent from the last to the next-to-last syllable).