Over extractor just blowing air out to ceiling.

Hello, I have decided to try and clean above the kitchen units as there is a gap between them and ceiling and full of stuck on greasy dust. I'm guessing it's from the extractor as it is simply a vent that points up and blows air out. Shouldn't this have a cover/funnel or something? It's not near an outside wall so can't go straight out but we been living here a year and the dust is horrible above it
https://ibb.co/XkTyh8z
https://ibb.co/fXVZL4g...

Over extractor just blowing air out to ceiling.