Gmail labels Google Mail Search

Gmail labels  When searching for emails, try the following filters :

^g: muted conversations (just like is:muted or label:muted or label:mute)
^p: messages marked as phishing
^op: messages automatically marked as phishing by Gmail
^os: messages automatically marked as spam by Gmail
^vm: Google Voice voicemail messages (just like is:voicemail or label:voicemail)
^io_im: important messages (just like is:important)
^unsub: messages that include unsubscribing options. Gmail offers to unsubscribe on your behalf
^cff: messages from your Google+ circles (just like has:circle)
^p_esnotif: Google+ notifications