I have been seeing cracks on my walls, and those cracks keep increasing, i will like to know the cause and appreciate any assistance on what to do to arrest the situation. Take a look at a pix of my living room wall

This is a failure of the foundation (Settlement).
There are a few things to be considered:
How old is the building? If relatively new, live with it for the time being for final settlement, b/c if you remedy it now, it will surely come back.
If the building is at least 5 yrs old, it can be remedied now. Let us know the age of the building so that we can start from there.

thanks for your prompt reply, goodman. The house is 4yrs