It could be for children. Kids usually love story books.
I believe it's aimed at families in general. Parents can read the stories to their young children, and older kids can read it on their own. It might also appeal to those who enjoy folk tales and stories with a touch of cultural heritage, so perhaps adults who are interested in such things are also part of the target audience.
The target audience for 'Uncle Yossi Big Book of Stories' is likely to be quite broad. It would be suitable for children as it can introduce them to the world of storytelling and different ideas. However, it may also attract adults who are nostalgic for the kind of stories they heard as children or who have an interest in the cultural aspects that might be present in the stories. Families as a whole could be the intended readership, as it can be a shared reading experience during family time, promoting family bonding through the enjoyment of these stories.