PDF conversion is never an easy task, usually copy&paste will ruin the original formatting. I don't know how you changed the PDF to Word, but try pdf conversion apps like pdf to excel converter
, PDF to Word converter
or online pdf to word service
may help. If the pdf conversion software is good enough, it can keep the original alignment exactly like the original PDF, but most of the time, if your pdf file has complex layout, the output file may change, even if Adobe Acrobat won't keep the formatting perfectly.