When you see these names, it usually means the software that created the PDF failed to embed the original fonts. Placeholder Names:

: Because your computer doesn't know what "F1" is supposed to look like, it may display the text as dots, boxes, or garbled symbols. How to "Fix" Missing CID Fonts

For exact F1/F2/F3/F4 matching, subscribe to (included with Creative Cloud). Search for “Adobe Ming,” “Adobe Myungjo,” or “Kozuka” – these are the real CID fonts behind those tags.