I think part of their problem is their codex is too large. The search engine can't correctly figure out how things are linked anymore since there is way too much data.
Take word like "monitor". Google thinks it is a computer display. It could also be a reptile, part of a roof, foldback speaker, a ship or about 50 other things. If the search codex shows a close enough association between a computer display and nearly every other use of the word, it is going to redefine the word into its own common use. You can find examples of this using terms for pipe organs which have a huge overlap with parts of CPU internals such as buffers, registers and accumulators are closely related in their respective fields.
I figure someone will come out with a search engine where the words then will have drop downs so the user can pick the type of thing they are searching on so they may be able to click on "monitor" and have one of the options "monitor - reptile"