Only 1 finding when asked for as many as possible?

API
1

Hello - i try to use this request to the API -

    resp = client.responses.parse(
      model = "gpt-4o",
      input=[
        {"role": "system", "content": """You are a helpful assistant.""",},
        {"role": "user", "content": """
Please find as many matches as possible for DHL in Germany for the same type and similar size companies
"""},
      ],
      text_format = OutputData,
    )

As you can see i try to ask for “as many matches” as possible.
But most of the time i only get on response / answer looking like that:

['IBM Watson Health', 'Hermes Germany GmbH', 'https://www.myhermes.de/', 'Hamburg, Germany']

Only very rarely (1 out of 10 runs i would say) i get a more comprehensive list like:

['IBM Watson Health', 'DPDgroup', 'https://www.dpd.com', 'Aschaffenburg, Germany']
['IBM Watson Health', 'Hermes', 'https://www.hermesworld.com', 'Hamburg, Germany']
['IBM Watson Health', 'UPS Germany', 'https://www.ups.com', 'Neuss, Germany']
['IBM Watson Health', 'FedEx Germany', 'https://www.fedex.com', 'Kelsterbach, Germany']
['IBM Watson Health', 'GLS Germany', 'https://gls-group.eu', 'Eschborn, Germany']

What can i do or how can i rephrase the prompt so i will get all the possible matches as output an not only one when running the request=