House flies are about as big as your fingernail. They like all foods left out on the counter. The coiled sticky traps that are hung from the ceiling is their Nemesis.
And it will stay sticky for years. So put it up and leave it until it is solid with flies. They can smell the sticky (even if you can't) and it attracts the flies to land on the surface, where they remain stuck and basically starve.
The liquid soap should have taken care of the little ones. That or a partial bottle of old beer poured in a dish and let it sit on top of a window ledge or on top of a cupboard. Sugar water in a dish may also attract them.
When really stuck for answers, try fly screens over the windows and keep the door closed.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.