Searching PDF file in DT

I have a question on importing PDF files.  I am using preferences whereby the files are saved to a database folder and the text is stored in DT.  I understand that the text is searchable by DT itself.  However, if I open the file in DT, it appears that this is in preview and I am unable to actually search the file for any words, i.e. the command Edit/Find— has all items grayed out. I am also concerned in that the new manual implies that there is a link from DT to the PDF file which now resides in  User/my name/Library/Application support/DEVONthink/Files.  Is there a direct link to open this file from DT, or do I need to navigate to it out of DT/ ???

You could use the commands “Open Externally” or “Launch”. But it’s not possible to search within displayed PDF documents currently and highlight the selection - Quartz does not provide such possibilities and Apple’s Preview uses a private solution.  >:(