Jonathan Wilkes has made a really nice documentation system with tags, meta data, etc with a nice searching and browsing interface in the 'search-plugin'. This is included in Pd-extended 0.43.4 by default. It can also be localized, but its a separate translation project from Pd itself (it shares basically no strings anyway).
If you haven't tried it already, go to Help -> Search (or Browser2.0 on certain versions). And then you'll probably want to translate it: https://www.transifex.com/projects/p/puredata/resource/search-plugin/
:-D
.hc