Of course six million bodies weren’t found, you idiot. You can’t simply leave bodies rotting in the open for five years, which was the duration of the holocaust, roughly. The vast majority were cremated. Towards the end of the war, when the Germans ramped up the killings in anticipation of losing the war, they had to resort to mass cremation, as the crematoria were backed up and the bodies piling up were beginning to rot. Even this didn’t suffice, though, and they had to resort to mass burials. However, when the SS retreated to Berlin, they subsequently dug up the mass graves and burned the bodies, trying to dispose of the evidence. They did their best to sterilize all evidence of the death camps, dynamiting the gas chambers and crematoria and doing what they could to get rid of the bodies.
The piles of bodies you see in photos are only the people who died AFTER the SS retreated. The holocaust didn’t end when the camps were liberated. 500 people a day died after liberation, from starvation and disease. All those photos were taken by the allies. There are only several photos of the death camps while they were in operation, taken clandestinely by the Sonderkommando at great risk to their own lives.
Two million Jews were executed on the spot by soldiers, police, and killing squads. Those bodies ended up in mass graves or crematoriums from Germany to the Ukraine. The other four million were almost entirely cremated, and the ashes were dumped on fields and into lakes and rivers.