This is the 6791st most frequent Polish word.
fus
Residue or dregs, often of coffee or tea.
Here, 'fus' again refers to coffee grounds, specifically criticizing the quality of the coffee which might produce more residue.
Kupujmy lepszą kawę, bo ta ma za dużo fusów.
Let's buy better coffee because this one has too many grounds.
Here, 'fus' is used to describe coffee grounds, often referring to the residue left after brewing coffee or tea.
Maria przeczytała fusy z kawy i przewidziała przyszłość.
Maria read the coffee grounds and predicted the future.
In this sentence, 'fus' refers to tea leaves left at the bottom of a cup, indicating the residue after brewing loose-leaf tea.