I have a mac. There is an included app that we use to open pdf, Aperçu. I realize I do not know the english name of that app… When you open a pdf with that app, you can show a left column with vignettes. It is absolutely possible to take vignettes from a pdf file and move them to another file, so it is quite easy to have multiple scores in one pdf file. I assume there is that kind of stuff on PC.
OS X 10.11.6, macbook pro retina Late 2013
Opera singer (lyric tenor), photographer, sound engineer, XeLaTeX user and a sometimes music engraver