Kid suffering from Eczema. A solution.

My 4.5 yrs son has eczema flare ups on lower legs. It started last year when we shifted our home; new place is dusty. There are mainly 4 spots that keep on coming back during COLD WEATHER. His elbows have couple of spots, but they don't cause issues and fade away when taken care of via extra moisturization. The issue is with the 4 spots on lower legs. They start as tiny bumps, then go on to become red lesions, and when he scratches (I do keep his nails short), the whole area becomes red and swollen. Sometimes it disrupts his sleep. I keep moisturizing these areas multiple times a day using Aveeno/petroleum jelly, but somehow the lesions come back even though his skin doesn't look dry. Had used prescribed steroid creams/lotions (Desowen, Mometasone Furoate) earlier, but not anymore as the problem does return every now and then. His diet is same as before all these started, so don't think it's food allergy. As child, I had similar issue, so could be hereditary. Please suggest a solution.