How to send and receive data with Eluetooth Low Energy?

Hi all!
I had module HM-10 buetooth low energy 4.0!
I write simple app for my phone using QtBluetoothLowEnergy to connect, send and receive data with module. It's connect ok but I can't send or receive data.
How can I send and receive data when it connected?
How can I send and receive data broadcast?
Many thanks!