This is the 153rd most frequent Estonian word.
sinna
The Estonian word "sinna" means "to there" or "to that place" in English.
In this sentence, 'sinna' is used to indicate the direction or destination of 'I am going'.
Ma lähen sinna homme.
I am going there tomorrow.
In this case, 'sinna' is utilized to identify the target destination whose distance is being inquired.
Kas sa tead, kui kaugel sinna on?
Do you know how far it is to there?
Here, 'sinna' specifies the destination to which the books should be taken.