I'm not sure I understand the details of your situation since your comments are very poorly written. Two monitors connected to a splitter will obviously display the same thing since they receive the same input from the computer. If you want to be able to display different apps on the two monitors, which seems to be what you want, then you need a video card with two outputs, typically a VGA port and a DVI port, or perhaps two DVI ports.
Do you have a video card with two outputs? If so, what type of outputs are they?