Text Indexes MongoDB, Minimum length of search string

I have created a text index for collection X from mongo shell

db.X.ensureIndex({name: 'text', cusines: 'text', 'address.city': 'text'})

now if a document whose name property has a value seasons, its length is 7

so if I run the find query(with a search string of length <= 5)

db.X.find({$text: {$search: 'seaso'}})

it does not return any value if I change the search string to season (length >= 6) then it returns the document.

Now my question is does the search string has some minimum length constraint to fetch the records. if yes, then is there is any way to change it?