Bluetooth not function well

I had purchase a Logitech X50 bluetooth speaker and a keyboard for my iPad Air 2 (IOS 11.2.6) but when I turn on the bluetooth for the speaker and keyboard my iPad can’t detect both of the device. I try to use the same speaker to connect for iPhone 8 and it work great. How come it can be like this as both also Apple product but it can’t even work well for the connection of Bluetooth speaker and keyboard?