How to search within T.O. results?

Let's say you have a join-type table occurrence that can locate just the record set you're interested in. So you go to a Results Layout with a GTTR (from a Base Layout) and can step forward and backward though the found records. Now you want to use a button-based script to search just those records for some particular phrase in a text field. You want to stay on the same layout and view the constrained results and step forward and backward within the new subset. Then you want to revert to your original found set that your table occurrence provided.

How can this be set up? Should the Results Layout be the basis for scripting the text search? -- or should you have the script operate on the primary table? (BTW, this is a managed application where the user never sees FileMaker's Status Area.) Do you always have to go back to the Base Layout and come downward again to get the original found data set back? Or stay on the Results Layout and use a script to restore the original set? Not much of what I have tried so far has worked,

A SECOND QUESTION: When on the Results Layout described above, what is the proper way to create a new record and have it display immediately as a member of the found set? My create script works fine, but the new record is absent until I come back down from the Base Layout via a GTRR.

Thanks in advance for any help with this.