ElasticSearch's text analyzer isn't semantic, but it does stemming and a few other transformations. Combined with the ranking of results by match, I can type in a couple of words or short phrase and get back a reasonable set of notes. That combined with the tags I used and linking means I can typically find the most relevant notes pretty quickly. It might be nice to have some ability for it to match synonyms of search terms given, eg. 'movie' and 'cinema'. I worry about overzealous collapsing of synonyms, for example 'film' can mean 'movie', but mostly they are different concepts.