There are times when you’re in need of searching your DEVONthink databases but don’t want to switch out of your current application or space. In System Preferences > Keyboard > Shortcuts > Services > Text, there is a service named DEVONthink Pro: Lookup… This will be active when you have some recognized text* selected in a document. Selecting the service from the current application’s menu > Services will open a full search window with the search already completed!
Adding a hotkey to the service using will allow you to fire this off very quickly and easily.
* Most, but not all, applications will work with services properly. However, the results are dependent on the application you’re in. For example, selecting a word in a PDF in a Chrome window may not detect text. But selecting text on a web page in Chrome may. YMMV.