Perhaps you should try some spelling variations:
"open regenerative syntax" » "open generative syntax", "open regenerative system", "open regenerative systems", "upon regenerative syntax", "die regenerative syntax", "bone regenerative syntax"
"non regenerative syntax" » "non generative syntax", "non regenerative system", "non regenerative systems", "_ regenerative syntax", "a regenerative syntax", "3 regenerative syntax"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"open regenerative syntax\") OR (\"non regenerative syntax\"))*".
• Removing quotes may allow a broader search: (( open regenerative syntax ) OR ( non regenerative syntax ))*.