Results for a query in Portal or AGOL seem to be limited to 1,000. Is there a way to remove any restrictions on the number of records returned for the search.
How To: Update the maximum record count for feature services in ArcGIS Online (esri.com)
Beat me to it!
Jose, the links by Dan and David only apply if you own the service, or have permissions to modify service properties. If you are simply a consumer of the service, there is no way to change or override that setting.