What do we want:
To make the boolean search usage extremely clear on the legal search pages
Why do we want it?
Because there is confusion around the different uses on the regular and advanced search interfaces.
Below is a mock-up of that includes two adjustments to the existing boolean search.
@patphongs I know we discussed modifying this further to remove the instructions from the "Find documents with..." pop-up, but I'd like to test this option first before removing those instructions further. My intention is to further clarify the instructions and make them a bit more clear before we remove them entirely. This would also be helpful on the legal resources landing page, where uses may not be aware that they can use those symbols. But I'm happy to discuss it further if you have reservations.
Designs:
In addition to clarifying the instructions for using boolean symbols on the searches for AOs, MURs, Statutes and the legal landing page search, there is also the addition of a tooltip for the Keyword search on the main search panels. This would work for each legal resource search where boolean search terms are used. Including: Advisory opinions, Matters under review and Statutes.


Next steps:
Maybe: Refine a keyword search by using AND, OR, "" - to expand or limit results.
I think it is a little confusing to call AND a symbol (but maybe I'm wrong), and since you can use these factors in combination, I think we should avoid the "or."
@AmyKort I updated the mock-up with your suggested text. If there are no other edits, I can move this to an implemention issue and create a testing ticket.
Here's the updated version:

@llienfec and @dorothyyeager What do you think?
Looks good to me.
For the keyword info box, I like the language change.
For the big box, I like the "or" in the explanation box. I'll be interested to see whether this will help with people using the symbols on the left hand side.
Looks good to me as well. I get confused on boolean searches so this seemed clear to me.
Awesome! Thanks @JonellaCulmer !
Great! Thanks everyone! I've opened an implementation and a testing ticket to move this work forward. Both are linked below.
Implementation ticket: https://github.com/fecgov/fec-cms/issues/2283
Testing ticket: https://github.com/fecgov/fec-testing/issues/112
Closing this ticket in favor of those issues.