To search text layers of DjVu -files

I would like to expand the system search to DjVu -files or find an alternative way to do this. My current OS X is Yosemite 10.10.2 but this can a Unix tool tool. DjVu contains an OCR text layer, making it easy to perform copy and paste and text search operations. The search is also more efficient than in PDF.

How can you search Djvu files also efficiently in a system search? I am open about tools. It can be Finder but I would prefer first efficient terminal tool.