Fetch work item search results: usage of top and changedDate

Hey there,
am trying to find matches for some keywords with fetch_work_item_search_results. Param top within WorkItemSearchRequest is limited to max. 1000, does this mean they're max. 1000 results that can be returned or max. 1000 work items that are even checked?
I'd also like to apply a filter to check only for the work items from the past week, but when adding the filter with System.ChangedDate following exception is thrown:
azure.devops.exceptions.AzureDevOpsServiceError: Unknown filter [System.ChangedDate] found.. Which filter could be used instead or is there no possibility to filter a specific timeframe without using WIQL?

sort_option = SortOption(field='system.id', sort_order='ASC')
for keyword in test_keywords:
    search_request = WorkItemSearchRequest(
        #filters = { 'System.ChangedDate': [ '@Today-7' ]},
        search_text = keyword,
        order_by = [sort_option],
        skip = 0, 
        top = 1000, 
        include_facets = False
    )
    work_item_search_response = search_client.fetch_work_item_search_results(search_request, project=project_name)

Commencez par les points d’entrée WorkItemSearchRequest et fetch_work_item_search_results présentés dans l’issue, puis consultez la documentation de l’Azure DevOps work item search API concernant la limite de top et les filtres pris en charge. Le travail est considéré comme terminé lorsque vous aurez documenté si top limite les éléments renvoyés ou les éléments recherchés, et identifié la manière prise en charge de restreindre les résultats par date de modification, ou indiqué clairement que WIQL est requis.