Sticky: Read this before Posting PDF Questions
No, "converting perfectly into DOCX" does not exist, and will not and cannot fix the problems inherent to using PDF.
The best any PDF-to-Word converter can do is make use of advanced and expensive parsing engines to make a best-guess at where the paragraphs connect, and I do not know of any such software. It probably does exactly what calibre does and uses a generic line unwrap factor. So you might want to think about checking for the odd split/joined paragraphs.
Either way, this is another common problem with PDF conversions (IIRC calibre does the same) -- it correctly unwrapped those two lines, but took the PDF at its word with the hyphen and linebreak, and assumed they were two words.