White noise works for most kids, like the others said, but if it doesn't, these tend to help.
1. Rock the baby gently and make soothing sounds
2. Dangling something shiny above them tends to work.
3. Try a bottle, sometimes babies get stomach aches and just need something to settle it, or to be burped.
4. There are chewing blocks, big plastic, but hollow, blocks tend to keep their attention fairly well.
5. If all else fails, they could have stomach issues, so a doctor would be a good suggestion.