OR

await prismaClient.objective.findMany({
      where: {
        patientId: id,
        OR: { // replace with AND makes no difference
          branchingOptionId: { not: null },
          conversationItemId: { not: null },
        },
      },
    });

 // generates: SELECT Objectives.id, ... WHERE (Objectives.patientId = 1 AND Objectives.branchingOptionId IS NOT NULL AND Objectives.conversationItemId IS NOT NULL)