Quote from Geom on April 9, 2016, 12:09
Help me please .it's my first time order.
Where is the packet RH311708779CN

This is what I found for you:

2016-03-30 16:46:42.0 Guangzhou Int'l Parcel Center received
2016-03-30 16:46:48.0 Guangzhou Int'l Parcel Center customs scan
2016-03-30 20:35:57.0 leaving Guangzhou Int'l Parcel Center ，next station 广商大宗
2016-04-01 01:30:34.0 Shanghai Transit Station export security scan
2016-04-01 10:06:06.0 Shanghai Transit Station export customs cleared
2016-04-02 01:15:00.0 arrive Shanghai Int'l Airport
2016-04-02 04:27:41.0 leaving Shanghai Int'l Airport going to next airport/seaport
2016-04-02 04:57:49.0 leaving Shanghai Int'l Airport going to next airport/seaport
2016-04-05 08:19:00.0 Shanghai departure

Everything seems normal for your parcel.
You should also look at this: China Post Airmail Parcel Estimate Arrival Time, on this site: http://track-chinapost.com/China_Post_Arrival_Time_Stat.php

Hope the above information will help you.