In Find in Files dialog box, by the File types dropdown list, please click the “>” button, then click “Current File”,
I am stupid, sorry.
I looked there several times and doesn’t see it till now.
(probably because it is greyed out for un-saved files like my test file)
I meant not “un-saved files” as it,
but rather “not yet saved for the first time files”
Thank you! I will try.