How to select pages to display

How do I select which pages to display in a post grid? I have created a grid that shows all pages but cannot select specific pages to show. I can add a keyword in the search parameter field and the grid shows pages relevant to that one keyword, but when I have attempted to enter 2 or more keywords, separated by comma, +, or space, it shows "no post found" message.

The post grid I am referencing is entitled:

"Event type - to replicate dropdown menu."

The page where this exists is:

http://www.entertainmentagency.london/event-type/

I am attempting to have the page display the same pages that are featured in the dropdown menu.

Thank you.