The Nag Hammadi scrolls were found in Egypt around the time of the Dead Sea ones. I believe they were written in the second Century by a Gnostic sect. The most famous one is the Gospel of Thomas which has some versions of parables found in the Gospels. This is the one some believe should be included in the Bible. There are a considerable number of Gnostic Gospels, Acts and other writings dating from the second century. The main teachings behind i all of them is that the world was created by an inferior God. A select few have a divine spark of imortality within them that must be set free from matter. Thge various Gnostic sects claimed that they alone had the secret knowledge to achieve this.
Following on from this they believe that Jesus did not come in the flesh but was some kind of Spirit, details vary. The Gnostic were condemned by some of the early church fathers as being heretics. Their teachings are more in line with Greek Philosopy than Scripture.