Perhaps you should try some spelling variations:
investment services » government services, treatment services, investment choices
investment period » investment series, investment policy, investment demand
trade investment » private investment, estate investment, trade adjustment
likert trade » likert scale, latent trade
kept capital » net capital, debt capital, term capital

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( h. likert trade investment services ) OR ( h. kept capital investment period ))~.
• Adding a wildcard symbol may retrieve word variants: (( h. likert trade investment services ) or ( h. kept capital investment period ))*.