If you have a recipient you would like to send a Thnks to that is not in your phone contacts you can still manually add their email address (or phone number) into the search bar and select them from the list on your Thnks mobile app.
You may also sync your mailbox contacts on Web or Mobile. Once synced, these contacts will appear as you start typing their name/email address.
For further instructions on how to connect your contacts, see this article.
Can't find your answer? Start a live chat or email firstname.lastname@example.org.