I've lost my iPhone what can i do

Ok so i had "find my iphone" set up and everything and i left it on the bus and some1 must of picked it up i think they have disposed of my sim because everytime i call it goes straight to voice mail i'm away for the week so i can't check find my iphone until like 4 days, so what if the thief restores the iphone will i be able to see where the iphone was just before it was restored or where the sim was disposed on find my iphone, what can i exactly do i have the serial number aswell does that help? I really want my iPhone back Help!

Use the GPS app text your phone and it should turn on.