Comparison to core [current-page:query:?]

Problem/Motivation

Please help me understand how this differs from the core [current-page:query:?]?

That said, I cannot seem to to get that core token to work anyway!

All I am trying to do is to have a view that creates a simple block that allowing me to rewrite and display the query string.

For example, with Search API in action, if I a, search for the word 'binary' then I would hit the page /search/staff?search_api_fulltext=binary then I want my Views block to display something like this...

Searching for 'binary'

If however I was searching for 'binary code' thenI would hit the page /search/staff?search_api_fulltext=binary+code then I want my Views block to display something like this...

Searching for 'binary+code'

Very, very simple but elusive!

Should I even need this module, shouldn't the core token be working in a View re-write?

I would really appreciate a little guidance here as I have obviously hit some kind of mental block!

Thanks