I need to find extension for mentioned wires but don't know how to google them, since I don't know their name.
Here is a picture:
I've always called them front panel header connectors. Some call it the header block on the board.
They sell extensions here.
They're called wires. Really, they're just copper wires.
Having said that, you may have more luck if you search on system panel cables/wires or motherboard cables/wires.