a question in soft topology

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The definition of soft topology is: enter image description here

My question is, isn't the soft topology in the folowing example lack the intersection and the union of two of it's sets? enter image description here

I mean, shouldn't the sets $\{\{\phi\},\{x,y,z\}\}$ and {{x,y},{x,y,z}} also be there?

here is the definition of a soft set: enter image description here