Possibly: Treat the search results as a folder and be able to search that; or simply a "Search in results" or "Refine Search" button.
My initial reason for wanting this BADLY was because I was using an old version. That didn't have the ability to add more conditions. So it was critical.
Once I got that update, I found that when I added a condition, it wasn't smart enough to search within the existing results. But instead started a whole new search. So it was slower, and used more resources.
And if my VM was loaded, searches could be a LOT slower. Ultrasearch slows WAY down when it doesn't have the working memory it needs. It is definitely NOT fast then. I can go to the fridge for a snack, and be back before it is done. I'm talking minutes.
In what role do you need this feature?
Sometimes we don't even know precise terms to look for when performing a search (bad memory or bad spelling in names..).
So looking with a general term or file type and then refining the results with a "search within results" might help.
Why do you need this feature?
quickly try different search combination to help find a file
What are the exact tasks you would like to accomplish with the feature?
See above for example
why would you prefer to search within the search results instead of extending the search query?
Possibly faster ? or lack of knowledge of search query possibilities
Would you please be so kind and supply us with some more information on why you need this feature and how you would use it? We would like to know in which role you perform your task, what you want to do, and why you need to do this / what is the final goal. You may use the format: As [role] I want to ... so that ...
And why would you prefer to search within the search results instead of extending the search query?