[AC Question]

I have a Samsung Galaxy S5 and want to send entire conversations from my messages to may email, not one message a a time.

[Rukbat]

Use an app like SMS to Text to make a text file of the conversation, then send that text in an email (you can share it from an app that reads text files or you can copy it and paste it into an email.) The listing of texts can't be sent as a single email, from the text app, because texts aren't stored as conversations, they're stored as single texts. The app stitches them together when you read them.