If you want to copy table from Google Document to Google Spreadsheet then you may struggle to paste it with the correct placement of the text, this issue is well known and hope Google fixes it soon.
Anyways there are two work arounds that you can try.
1) First copy the table from Google Spreadsheet and then paste it to Microsoft Excel, and then again copy this table from Microsoft Excel to your Google Spreadsheet.
2) Publish your Google Document. You can do it from "File" menu > "Publish to the web..." and then click on "Start publishing".
And then copy the "Document link", which will look like:
Screenshot of my Google Document:
And now use the copied Link of Document in Google Spreadsheet with ImportHtml formula.
Try the following formula in your Google Spreadsheet:
replace the above link (marked with green color) with your spreadsheet link.
So now you will have the table imported from your Document to your Google Spreadsheet, you can copy this table and paste it in other cells or other sheet by right clicking and select "Paste special" > "Paste values only".
I hope this helps,