Is there a way to narrow selections with a search pattern?

[Avi-D-coder]

I would like to be able to narrow my selections by providing a pattern. Matches within my prior virtual selections would be my new virtual selection set.

Filtering selections is also useful. Selections containing the pattern remain selected, all others are discarded.

[Beloin]

Could you please show an example of what do you mean by narrowing yours selections?