Since the Gospel of Thomas agrees with Acts, why can't we consider it Canon?

Not only that, but Thomas has more parallel verses with Mathew, Mark, and Luke, than the Gospel of John has. Mathew, Mark, and Luke are called the "synoptic Gospels" because of these many parallel verses. I submit that Thomas should be designated the fourth synoptic Gospel. I think that Mark and Thomas are actually the oldest of the Gospels.