It is still possible: You scan and OCR, then you can select the text (using the "Selection Tool", which you can find on the toolbar to the left of the hand tool), copy and then paste.
If you are not satisfied with the OCR quality, you may want to look at your scanner settings (e.g. increase the resolution, or scan in grayscale instead of black&white or vice versa) to see if that improves the OCR output. If it does not, then you are unfortunately stuck with this level of OCR quality, and your only option is to switch to a dedicated OCR application. I have actually gotten pretty good OCR results from Acrobat XI, but it always depends on the quality of your source documents, and it may also depend on the selected language: My results are with English text.
If you need a more advanced OCR package, I know that Abbyy's FineReader is a very good package.
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
http://www.khkonsulting.com