Unfortunately, the amount of detail you get from a Drop log won't necessarily tell you whether it should be permitted or not as that's a matter of the specific policy your organization has set.
That said, you can easily find all the drops and find "top talkers" and the like in SmartLog.
Use the search term Action:Drop in order to find all the recent dropped and logged packets.
You can then drill into the top sources/destinations as appropriate.
As you click items under the "Tops" tab on the right, your search terms will be adjusted to show only packets that match that criteria.