The autocomplete suggestions are currently based on wikidata terms (labels or alias) where the beginning matches the search string.
This includes suggestions like "Caterpillar-induced plant volatiles remain a reliable signal for foraging wasps during dual attack with a plant pathogen or non-host insect herbivore." (Q42004108) and an awful lot of others.

Those kind of absurdly-specific suggestions should not show up, especially since those are not terms that will ever be associated with an image.

A few possible ideas to mitigate these:

• filter out suggestions that'll yield no results
• filter out "instanceof:scholarly article" items
• only autocomplete the current word