Lesson learned. This weekend I will update the web site to default EMS shipping with higher freight 20 USD. For the returning customers with good transaction experiences, you can save money by requesting regular air shipping by email in 2 hours after order placed via PayPal. The shipping cost will be based on the actual and the extra will be partially refunded.
Both EMS and regular air shippings can be tracked. However, the regular air shipping is slower and varies within 7-30 days for most of the countries.
I hope you can understand the trouble caused, in order to improve experience.