`dianyou-group-make-nnir-group' to search mails.
`dianyou-insert-email-address-from-received-mails' to insert email address.
`dianyou-switch-gnus-buffer' to switch between gnus buffers.
`dianyou-paste-image-from-clipboard' to paste image from clipboard.
`dianyou-email-view-in-browser' to view the body of email in external browser.
`dianyou-email-view-in-web-ui' to view the email in its web UI.