Why don't we have any records of what Jesus said and did during the 40 days after the Resurrection (Acts 1:3).?

Answer 1

Matthew 27:50-53; Mark 16:7-8, 12-20; Luke 24; John 20-21

All of these passages outline what Jesus did in the days following the resurrection. We know he remained on Earth for longer than 8 days according to these passages. He talked with his disciples, ate with them on occasions and was seen by countless witnesses before ascending back in to Heaven.