Complex sentence: Besides the refrain of the song beginning with the words "Bhaja Govindam", Shankara is said to have sung twelve verses, hence the hymn bears the title "Dvadasamanjarika-Stotra" (A hymn which is a bunch of twelve verse-blossoms).
Split into simpler sentences: Besides the refrain of the song beginning with the words "Bhaja Govindam", Shankara is said to have sung twelve other verses. Hence, the hymn bears the title "Dvadasamanjarika-Stotra" (A hymn which is a bunch of twelve verse-blossoms).