How to create preview snippet for website in Google Search ?

You may create your custom preview snippets for a website with the help of this nice plugin: https://wordpress.org/plugins/all-in-one-schemaorg-rich-snippets/

Please read this manual about how to use this plugin:
http://www.wpbeginner.com/beginners-guide/beginners-guide-how-to-use-rich-snippets-in-wordpress/

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