How can I query by document subject when creating a collection?

Plone Support Add-on Development
1

I need to get the last 10 items with the subject (keywords) Exercise Plan' for a specific collection. Currently, I'm usingplone.app.querystring.operation.string.subject`, but it's not working. Any ideas?

  collection_data =  {
        "exclude_from_nav":True,
        "contributors":data["contributors"],
        "text":RichTextValue(data["text"]),
        "allowDiscussion":data["allowDiscussion"],
        "query":[
            {
                "i": "subject",
                "o": "plone.app.querystring.operation.string.subject",
                "v": "Excerise Plan"
            },
            {
                "i": "portal_type",
                "o": "plone.app.querystring.operation.selection.is",
                "v": [
                    "News Item"
                ]
            },
            {
                "i": "review_state",
                "o": "plone.app.querystring.operation.selection.is",
                "v": [
                    "published"
                ]
            }
        ],
        "sort_on":data["sort_on"],
        "description":data["description"],
        "customViewFields":data["customViewFields"],
        "sort_reversed":data["sort_reversed"],
        "tableContents":data["tableContents"],
        "limit":data["limit"],
        "presentation":data["presentation"],
        "defaultpage": data["_defaultpage"],
        "subject":data["subject"],
        "atrefs":data.get("_atrefs", {}),
     }

    obj = api.content.create(
        type="Collection",
        title=name,
        id=id,
        safe_id=False,
        container=container,
        **collection_data
    )
2 
  query = [{
        'i': 'Subject',
        'o': 'plone.app.querystring.operation.selection.is',
        'v': ['Lorem', 'Ipsum'],
    }]

I found the snippet above in the file below.

https://github.com/resa89/imusite/blob/64763cac5e5cbadd169a6d76905817f45b05687e/buildout-cache/eggs/plone.app.querystring-1.0.8-py2.7.egg/plone/app/querystring/tests/testQueryBuilder.py#L77