What you want I don't think is possible.
You can save in ODT and SVG format that are editable but the results are not good.
However, if instead of saving the SM file as PDF, the PDF molds with the virtual printer you want (for example Microsoft Print to PDF, which is already present in Windows systems, or others that you can install as PDFCreator etc ...) Get a PDF file in which the text is searchable, the quality is vector (does not lose quality and the file is less heavy).
This file would also be changed (without too many expectations) if loaded into Inkscape or LibreOffice.
In LATEX pdf pages can be entered in documents easily and without loss of quality.
sergio