This is the 11th most frequent Polish word.
tym
The Polish word "tym" means "this" (instrumental case) or "that" depending on context.
Here, 'tym' means 'this' and refers specifically to 'the shop' being mentioned.
W tym sklepie są najlepsze owoce.
In this shop, there are the best fruits.
Here, 'tym' refers to 'what I like/subthing or activity'.
Zajmuję się tym, co lubię.
I am engaged in what I like.
Here, 'tym' serves as the instrumental form of 'to', meaning 'this', referring to the problem.