2 External Monitors - envy m7

[NH551]

I have two external monitors I'd like to use with my notebook PC (hp envy m7-k211dx).

First, I tried using a box that plugs into the laptop and allows for two more hdmis to plug into it. I want to say it's an hdmi splitter, but I could be wrong on the actual term. Anyhow, I learned that the hdmi port only allows for one display. It treated all the screens as one display (even when I chose the option extend display -  in that case only the main notebook screen would work)

Next, I purchased a USB to hdmi and that one isn't registering the second monitor at all. 

How can I get the two external monitors to work independently (it's fine if one of them is a duplicate of the laptop)?

Note: Even when I use just one monitor via HDMI, it won't allow me to do anything except duplicate that monitor. The display shows as 1|2 instead of the notebook being 1 and the monitor being 2. 

Product number: J9K05UA

[banhien]

@NH551 

Your machine is an HP ENVY m7-k211dx , its specs

           https://support.hp.com/au-en/document/c04556394

If you wish to have 2 or more external monitors (and notebook monitor - total 3), please enter your requirement on the following link and it will find for you few USB-A DisplayLink Certified options on market today including some HP products (you can select HP before Search)

                             https://www.displaylink.com/products/universal-docking-stations

>>>> It treated all the screens as one display

That is TRUE, you can't extend monitors, you can only see them duplicate.

Regards.