It's from "The First of The Gang To Die" by Morrissey.
Is "thrown over" here mean toss something? Or is it mean abandon something?
Could you explain it to me in simple terms please?
No, throw light on is a standard phrase for shining on something, see Oxford Thesaurus. In my opinion, cast light is more frequently used.
(I'm not entirely convinced, that this is the most appropriate section of SO, English Language comes to mind.)
