Keyword search plugin
I would like to have the same keyword search plugin, could anyone tell me what is the plugin?
This is not a plugin, this is wpForo built-in search widget and search page.
The search widget is available with all wpForo widgets in Dashboard > Appearance > Widget admin page, you can put it in wpForo sidebar or in the forum page sidebar:
The search page is available if you add this URL part to your forum base path:
An example of our search page: