The criteria for combining deliveries is:
1. Same delivery date
2. Same ship to party
3. Same plant.
4. Same shipping point.
In your case, the Purchase order has lines with different delivery dates. Hence it cannot be combined into one delivery.
Moreover, even if you were to combine lines with different delivery dates into one delivery, the problem is that one delivery document can only have 1 planned and actual goods issue date, not one date per line item.
Please explain the business process more clearly so that an alternative solution may be suggested