Perhaps you should try some spelling variations:
investment period » investment series, investment policy, adjustment period
water investment » water investments, after investment, rates investment
payment series » payment services, payments services, payment service
melt water » salt water
dept rate » deposit rate
heat rate » flat rate

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. melt water investment period ) OR ( h. ((dept rate) OR (heat rate)) payment series ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( h. melt water investment period ) or ( h. ((dept rate) OR (heat rate)) payment series ))~".
• Adding a wildcard symbol may retrieve word variants: (( h. melt water investment period ) or ( h. ((dept rate) OR (heat rate)) payment series ))*.