There could be several reasons why a product is on one website and not on another one:
The product might be ready for a specific country but not yet ready for another one. Also, it is possible that this product is not available in that particular country due to several possible reasons; exclusivity issues; manufacturer’s request; certification and more. It is also possible that it will be available in the future but cannot be shipped to a specific region right now.
Fortunately you have the option of placing an order on another RobotShop website which lists that product, but please be aware that you may have to pay higher shipping fees, unnecessary taxes and duties by doing so.