Some of your eggs do show veins, and some don't. I would like to suggest you read this great article by Sally Sunshine. It has pictures of candled eggs, at different days. Great reading.
https://www.backyardchickens.com/ar...hatching-chicken-eggs-aka-hatching-101.64195/
WISHING YOU BEST,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,and
