Move closer to windows
Since there will be less light, move your plants to be closer to windows. On a dark, cloudy day, plants several feet away from windows get almost no light. Put them in front of the brightest window – south or west-facing in the Northern hemisphere, north or west-facing in the Southern hemisphere.
I suggest wiping off the leaves weekly. This will remove the dust and dirt blocking the light and allow the leaves to absorb the maximum amount of light.