Hello  @AnnaItaly 

Thank you for asking. You could use one wired powerline line unit as main adapter that connected to router, and use other 3 adapters as extenders. 

Here are some tips to manually pair first two powerline units

• Put 2 powerline unit in the wall sockets, in the same room, and pair them: 

Paring Note:  press Pair button only for 1 sec, Power Leds should be flashing on both powerline units in pairing process. ( if the Power Led does not blink, press it for 1 sec again)How to secure (pair) the Powerline Network?

• Then you could pair the 3rd and 4th adapter with the one of the working powerline extenders one by one. 

To add more powerline unit, you could download tpPLC Utility , and add more devices to the network using tpPLC Utility (new logo)?