1. This is the tracking of your parcel:
China Post Register Air Mail Tracking System
Parcel No.RF372805607CN tracking result
2016-10-05 17:17:06.0 Electronic Data Received
2016-10-06 21:00:20.0 China Post Group 浙江省Yiwu city 邮购配送公司 received
2016-10-07 01:10:00.0 China Post Group 浙江省Yiwu city 邮购配送公司 customs scan
2016-10-07 01:25:00.0 leaving China Post Group 浙江省Yiwu city 邮购配送公司
2016-10-07 14:03:23.0 Yiwu Transit Station export security scan
2016-10-07 14:41:42.0 Yiwu Transit Station export customs cleared
2016-10-08 03:21:00.0 arrive Hangzhou Airport
2016-10-09 03:16:10.0 leaving Hangzhou Airport going to next airport/seaport

2. I also found this:
International Mail# RF372805607CN Tracking Result
Summary
Tracking number Origin Destination Status
RF372805607CN CHINA NETHERLANDS On route

History Detail
Local date/time Activity Location Remarks
06-Oct-2016 20:57 Received by Post Office 32206600
07-Oct-2016 16:59 Departure export customs CNYIWA

3. So according to the above tracking your parcel departed China and is On Route to the Netherlands. Normally estimate arrival time for European country is 3 weeks.

4. I was not able to track your parcel on the NL Post site because you are the only one that can. To me according to the above tracking your parcel is fine. If by next Friday the 28 Oct, you can not track your parcel on NL Post, then you should contact seller and tell him you have not receive your parcel.

Hope this help