When connecting your Google accounts to folk, you need to make sure to give the right permissions to folk, so that folk can access your source and correctly import the contacts and their interactions.
If you have connected a source, but no contact was imported, it probably means that we have insufficient permissions on your source.
In that case, you just need to follow these steps:
Go to your Settings > Accounts
Click on the "+" to add your gmail source again
On the Google permission page, make sure to check all the boxes to give the right permission to folk to access your source
Then your contacts, will start importing correctly and appear in the Search panel.