I saw that the dropdown of keywords in Advanced Searches was added per another user's request. I think this is great and helpful, but it has limited some other features that I used to use a lot.
I do miss when we used to be able to type in partial Keywords for searches. We use keywords very heavily and have prefixes that we use to categorize them. If I had the ability again to run searches for Contact Keyword - Keyword - Does Not Contain - RS, for example, I could quickly identify our clients who are not currently set up with a Review Schedule Keyword (RS May Review.. etc). I have created an immense Quicklists that has "Not Equal To" RS [each month] and other work arounds in the meantime, but I still think having the ability to write in as well as the dropdown option in searches would be helpful.
The suggestion may be planned, but there is no timeline on this feature being added.
This suggestion is remaining open and can continue to gather votes and comments!