Philippians 4:8 says,
“Finally, brethren, whatever is honorable, whatever is right, whatever is pure, whatever is lovely, whatever is of good repute, if there is any excellence and if anything worthy of praise, let your mind dwell on these things.”
Do you want peace of mind? This is how, do not dwell on the issues of life, instead dwell on the true, pure and excellent things in life. View life with a positive attitude not a negative one.