how to search through plugin in wordpress cimy-user-extra-fields?

It’s not clear what you are trying to acheive … but CIMY extra user fields is a good plugin and using any sql editor (like SQLyog or PHPMyAdmin) you can browse your WordPress database tables.

You’ll see that CIMY creates and stores all this information in the WordPress database. You can find a lot of helpful material on the plugin homepage

To retrieve the information stored in the database you will need to use $WPDB function