Use all in one pavilion as a second monitor

Hi guys,
Does anyone help to solve my problem in connect all in one HP computer to HP laptop? I have a HP Elitebook work laptop and i would like to use my personal all-in-one HP Pavilion as a second monitor when I work from home. I tried to use both the VGA, HDMI cable but it doesn't work.
Searching in forum I can only find that everyone use All in o e computer as a main computer not as a second monitor.Appriciate if someone can help me solve the problem as I need 2 screens in my work.
Thanks