You can't do this in basic mail,only in full yahoo mail version. If your in basic mail there is a link above the Inbox to switch to newest yahoo mail. Search for the sender then tick the select all box.
All messages should be selected. Click the Delete button with the trash icon,all emails for that sender should be deleted.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.