Perhaps you should try some spelling variations:
"open resource software" » "open resources software" (Expand Search)
"open reresources software" » "open reresourcess software" (Expand Search), "open resources software" (Expand Search)
"open reresourcess software" » "open reresourcesss software" (Expand Search), "open resourcess software" (Expand Search), "open resources software" (Expand Search)

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("open resource software") OR ((("open reresources software") OR ("open reresourcess software"))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"open resource software\") OR (((\"open reresources software\") OR (\"open reresourcess software\"))))".
• Removing quotes may allow a broader search: (( open resource software ) OR ((( open reresources software ) OR ( open reresourcess software )))).
• Adding a wildcard symbol may retrieve word variants: (("open resource software") OR ((("open reresources software") OR ("open reresourcess software"))))*.