I use Acrobat Pro 11.0.09 on Mas OS X 10.9.5 (though I have also verified that it happens on OS X 10.10 on a different computer). I can make Acrobat crash by opening a file, searching for a term not on the current page, and then opening a different document.
As an explicit example, though this works with almost unfailing consistency, if I open the Acrobat XI manual (at http://helpx.adobe.com/en/pdf/acrobat_reference.pdf), search for "workspace" immediately (note that "workspace" is on page 2, so that you have to still be on page 1), and then open the Illustrator reference (at http://helpx.adobe.com/pdf/illustrator_reference.pdf), Acrobat crashses. Every time.
Yes, using Advanced Search avoids the problem but it is much slower and more inconvenient.
It is astounding that a major piece of software can crash so reproducibly and simply.
