Convincing parents to invest

Hi all, As the title goes, how do I convince my parents to invest? Luckily they have a decent pension fund that may be just enough to sustain living back in our home country which I would consider LCOL. However, my issue is that they are just cash savers. No other investments and they cannot grasp the value of investing. I’ve tried explaining the effects of inflation and that there are other investing opportunities that are low risk but they just don’t get it. They are retiring in about 5 years