dig out:
dig somebody/something out (of something)
1 to remove somebody/something from somewhere by digging the ground around them or itMore than a dozen people were dug out of the avalanche alive.
2 to find something that has been hidden or forgotten for a long timeI went to the attic and dug out Grandad's medals.
dig up:
dig something up
1 to break the ground into small pieces before planting seeds, building something, etcThey are digging up the football field to lay a new surface.
2 to remove something from the ground by diggingAn old Roman vase was dug up here last month.
3 to discover information about somebody/something
Tabloid newspapers love to dig up scandal.
**reference:www.oxfordlearnersdictionaries.com