We are sorry for the delay in response to your query.
As mentioned that the pdf was converted to word and it doesn't open in Google Documents and the quality is also not good. So does it happen with all the word document created?
There are couple of possibilities that might be causing this problem-
1- The font used to create the pdf file has not been embedded or missing in the MS word.
2- The quality of converted document depends on the quality of pdf document you start with. If the text are garbled then you may read the related help document where its reason is explained in details- Text is garbled in a converted file | Adobe Export PDF
3- If working on desktop application, then check for the update. Open Adobe Reader>Help>Check for update.
4- If the document doesn't open on Google Document then check with a different browser.