Steve on 05 Dec, 2018 10:23 AM
welcome to the GPGTools support platform. Sorry you are having problems using GPG Suite.
Please update to the latest stable GPG Suite 2018.5, e.g. via System Preferences > GPG Suite Preferences > Updates.
Could you try and select a key server from the default list in GPG Keychain > Preferences > Key server and then repeat your key search. Does it then work? Are you able to select a key server from the default list?
PS: To benefit from the latest security fixes from apple, you may want to check for pending macOS updates in the MacAppStore. General info about Apple security releases including the latest macOS release.