Perhaps you should try some spelling variations:
"support der interaction series." » "support der interactions series.", "support der interaction studies.", "support der interaction terms.", "support der interaktion series.", "support dem interaction series.", "support user interaction series.", "support de interaction series.", "support under interaction series.", "support deep interaction series."
"support urban sanitation services." » "support rural sanitation services.", "support carbon sanitation services.", "report urban sanitation services.", "supply urban sanitation services."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("support der interaction series.") or ("support urban sanitation services."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("support der interaction series.") OR ("support urban sanitation services."))*.
• Removing quotes may allow a broader search: (( support der interaction series. ) or ( support urban sanitation services. ))*.