We use Google Universal Sentence Encoder which operates on TensorFlow.
It's impressive because it can handle multi-word "keywords", which ends up
being forgotten a lot in planning, but critical in actual use. It's
pretrained on several languages already by Google so you don't have to look
for a source corpus. A lot of alternatives make you go do something like
grab a bunch of Wikipedia, or they provide you with English-only source
corpus of the top 50,000 articles there. This is way ahead of those