wp tables not showing in tables list

I need to search and replace my databases with https:// to be replaced by https:// as my images are insecure at the moment.
I have activated the Better Search and Replace plugin, and when I open it in the tools menu the tables list does not show any wp tables. They all have a different prefix (ppo), and when I search and replace with https:// it tells me no replacements were found or made.
Why does the list not show any wp tables?