Go to -> Upload your PDF -> Open with "Google Docs." This preserves most text. Alternatively, use ilovepdf.com/pdf_to_text (free, no signup).
: For users comfortable with running scripts, this open-source TNSFileConverter can convert PDF, JPG, or PNG files into .tns files locally on your computer. pdf to tns converter free link
However, with the open-source nsPDF script or the TI-Planet web tool, you can convert dozens of pages in seconds. Just remember: and always scan downloaded files with VirusTotal. Go to -> Upload your PDF -> Open with "Google Docs