Trying to get a mortgage in US

My wife and I teach abroad, and have for the last 5+ years. We are both US citizens, and would like to move back to the US soon. We have looked at houses when we come back to visit and are trying to get approved for a mortgage to man an offer. No one seems to approve us because we reside outside the US. And then when we move back we will technically be unemployed since it’s the summer time. We will be applying to public schools in the area, so no one again will approve us, it could take a couple months to find a job. Any help? We would like to buy a house to move back into because coming back and renting will just eat into our house fund. I never thought it would be so hard to buy a house being a US citizen. Any info will help as we are first time home buyers. Thanks!