Why Are We Not Able to Detect Aliens?

There is no unambiguous evidence that we have found aliens in the past, he says. Some carvings on pyramids or rocks seem to depict alien visitations but it's not clear if they are real and/or even human. So a so the question is, why are we not able to detect alien life? If it is, if it should be so widespread and common in the universe? Well, maybe we are not evolved enough. Maybe we are too primitive. Most likely, we are still a very primitive species, right? He adds.