Perhaps you should try some spelling variations:
"descriptions based" » "description based", "descriptor based", "descriptions a"
"descriptive phase" » "descriptive case", "descriptive plates", "descriptions phase"
"descriptors based" » "descriptor based", "description based", "descriptors a"

Try widening your search to All Fields.

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: (("descriptive phase") OR ((("descriptions based") OR ("descriptors based")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"descriptive phase\") or (((\"descriptions based\") OR (\"descriptors based\"))))".
• Removing quotes may allow a broader search: (( descriptive phase ) or ((( descriptions based ) OR ( descriptors based )))).
• Adding a wildcard symbol may retrieve word variants: (("descriptive phase") or ((("descriptions based") OR ("descriptors based"))))*.