White stuff on hamster's fur?

[ShadowNinjaHamster]

Hello,
my dwarf hamster has some kind of white stuff in his fur. I can't see it with a naked eye, but I noticed it when I took a picture of him.
When I zoom in through camera I can see some white stuff on his fur. Can it be paper bedding?
I didn't see any movement. I tried to clean his fur with my hand as much as I could.

Another vet visit if it remains there? For real, with naked eye I can't even see those white things, whatever they are. Should I do another full cage clean and see how it goes? So far I've been spot cleaning and maybe I haven't done a good job at it?

Edit: I'll do another deep cage clean and see if I can find anything. Could it be paper? Could it be some food? Walnuts? Parasites?
I looked at photos from yesterday and even zoomed in photos were completely fine.

Edit: Checked now. Gone. There aren't any white things on his fur anymore. I zoomed in as much as I could.