Hi Xiaochao,
When using test accounts, the TargetingIdeaService will return dummy data. You may refer to
this guide for more information. When retrieving targeting ideas against a Production account, you will be able to compare the results to those from the Keyword planner as mentioned
here.
Could you please share the complete SOAP logs for the second scenario along with the client Customer Id used, so I can take a look? You can reply back via Reply privately to author option.
Thanks,
Bharani, AdWords API Team