How Do I Eliminate Suggested Email Addresses from Yahoo Mail App?

[avery1317]

When I compose an email in the Yahoo Mail app and type a letter, any letter, in the "To" field many, many suggested email addresses appear that are not in my contacts. I have tried selecting them but after they become highlighted no options are offered. I have looked in the contacts list on my phone and they aren't there. I've cleared the cache in the app. (I didn't clear the data since I didn't want to screw up the installation but since this has happened on my last two phones I suspect that it has to do with my Yahoo account not data on the phone.) I've gone to the desktop version of Yahoo mail and see no options there. And when I'm sending mail from Yahoo mail on my desktop this does not happen. I've gone to google.com/contacts and they aren't there. Some of them I recognize as ones I possibly received or sent an email to in the past but way in the past. And many I don't recognize. I've searched the internet and the Yahoo site to no avail. Maybe sometime in the past there was a setting to save all email addresses I sent an email to but I don't see that now and don't know where they are saved. I have a Moto X with Kitkat. Thanks in advance.