My Nexus had a couple hairline scratches. I tried all of the fixes that you find on google and nothing worked. Luckily I was having data issues so I needed to get a replacement anyway. As soon as I got the refurbished phone I got ghost armor for the screen... wasn't taking any more chances.
So, to answer the question... I don't think anything will get the scratches completely away. Something like ghost armor might diminish its appearance though.