Perhaps you should try some spelling variations:
"comparative pavement structure mater" » "comparative management structure mater", "comparative government structure mater", "comparative judgement structure mater", "comparative government structures mater", "comparative management structures mater", "comparative pavement structure matter", "comparative pavement structure matters", "comparative pavement structure after"
"cooling requirements case history" » "holding requirements case history", "filing requirements case history", "borrowing requirements case history", "cooling requirements based history", "cooling requirements core history", "cooling requirements race history", "cooling requirements trade history", "cooling requirements state history", "cooling requirements life history"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("comparative pavement structure mater") or ("cooling requirements case history"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("comparative pavement structure mater") OR ("cooling requirements case history"))*.
• Removing quotes may allow a broader search: (( comparative pavement structure mater ) or ( cooling requirements case history ))*.