I did not activated my new iphone and it has stolen within 13 days,can i found?

If you did not activate the "find my" app, then I do not think so.

https://support.apple.com/en-us/HT201472

DDBBSR wrote:

I have purchase invoice with the box also ,so still can be possible ?

Activating Find My can only be done on the device itself. It cannot be enabled remotely.

If you bought AppleCare+ with loss and theft coverage, or have Other insurance, you can see about making a claim.

If you did not activate Find My iPhone, there's nothing you can do to track it. Report the theft to the police.

~Lyssa

Unfortunately no.