Hello, I got a "F" visa recently with six months multiple entries,but each 30 days I've to exit from China.Can I extend my duration of stay or renew the visa in chengdu,China within 30 days after I arrived in China by the way I got my Chinese visa in India traveling to chengdu this month30th, my company provided me documents to get visa which is in chengdu if it's possible( renew visa or extend duration) what's the process ,what kind of docx they need?