Inner peace is to be achieved by the remembrance of Allah. The Quran even tells us that “Verily, in the remembrance of Allah do hearts find rest.” (13:28). Many people try and search for other ways to find inner peace and they fail.
As Muslims, we should be very confident that when bad things happen to us, it is for a good reason. Of course Allah knows what is better for us and we have to believe that. Often when people are in need they are driven to prayer. When we have a lot of good things in our life, we often forget Allah.
The real content is not in possessions but in inner contentment. Of course we can have some great possessions and be content with them but the more we have, the more we will worry about this worldly wealth.