hi @Gal_Malul ,
nope, the Coda documentation tell us that it only deals with the USA interpretation of a working week. I already suggested to update this function to cover a diverse cultural context. Maybe you can suggest it as well 
You need to write your own function for this like the one below
the other tricky part in any coda set up is the weekday() logic. My default value is Monday as the first day of the week, thus the IsoWeekday(), In the coda realm one function can output two outcomes, based on a setting. I hope they fix this sooner than later, it is a quirk. To avoid this, you can use WeekdayName() and filter on this instead of the number related to weekdays.
Enjoy your second day of the working week, mine just got started. Christiaan
ps. maybe easier to read 