Perhaps you should try some spelling variations:
government services » government securities
investment period » investment series, investment policy, investment demand
fixed government » dated government, free government, limited government
based investment » fixed investment, best investment, bond investment
test based » forest based, result based

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( h. agent fixed government services ) or ( h. test based investment period ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( h. agent fixed government services ) OR ( h. test based investment period )).
• Adding a wildcard symbol may retrieve word variants: (( h. agent fixed government services ) or ( h. test based investment period ))*.