Actually, no.
Smetana just means "cream", and the word itself sounds "sweet" when you hear it. Sour cream would be "(za)kysaná smetana"![]()
In Russian cream is slivki, and smetana is sourcream. And by sweet you apparently mean diminutive, like yablochko, polotentse.
"Hus(a)" is goose, yes, but I have no idea what "žižka" (that's /zhishka/ or some such transliteration nonsense) means.![]()
It's apparently from adjective zydkij(aja) - "liquid". In Russian it would be something along the lines of "squishy".