First Locate the source. I would see if your gutter might be leaking or possibly the downspout isn't letting the water get far enough from the foundation (8Ft). I would Check the grade of dirt on the foundation. The first 6 -7 ft of ground around the foundation should slope away at a rate of 1" every foot, and at least 3/4" beyond that. If the cracks in the floor are under 1/4" then use a waterproof masonry, use huydralic cement for larger cracks. And last resort would be to install a Foundation drainage system. I hope it doesn't come to that. Good luck