Why are there no contemporary writings about Jesus when he performed miracles?

My question is rather simple, given that in his time Jesus performed miracles, why don’t we have (as far as I know) any contemporary writings of Jesus, how do you explain that nobody in his time thought it was useful to talk about the magician who performs miracles? And yet we have the writings of kings, etc., which attest to their existence without (practically) the slightest doubt? Of course they’re kings, but we’re still talking (if it’s true) about a guy who performed real miracles.