Thich Nhat Hanh said this quote

Worrying does not accomplish anything. Even if you worry twenty times more, it will not change the situation of the world. In fact, your anxiety will only make things worse. Even though things are not as we would like, we can still be content, knowing we are trying our best and will continue to do so. If we don't know how to breathe, smile,and live every moment of our life deeply, we will never be able to help anyone. I am happy in the present moment. I do not ask for anything else. I do not expect any additional happiness or conditions that will bring about more happiness. The most important practice is aimlessness, not running after things, not grasping.