Gmail's Option for Excluding Chats from Search Results
Gmail's advanced search box has a new option: "don't include chats". If you click the checkbox, Gmail will append to your query: "-in:chats".

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To see the advanced search box, click the small arrow icon from the Gmail search box. It's an easy way to use powerful Gmail features if you don't want to manually add operators (https://support.google.com/mail/answer/7190?hl=en) like from:, to: or has: to your searches. You can also create filters.http://feeds.feedburner.com/~r/GoogleOperatingSystem/~4/F43ViGLwPRc