Perhaps you should try some spelling variations:
"rail projects air force" » "capital projects air force", "rail projects aims force", "rail projects asia force", "rail projects a force"
"road projects air force" » "road projects aims force", "road projects asia force", "road projects a force"
"a project based force" » "a project based fire", "a project based free", "a project based face"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("rail projects air force") or ("road projects air force"))) or ("a project based force"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("rail projects air force") OR ("road projects air force"))) OR ("a project based force"))*.
• Removing quotes may allow a broader search: (((( rail projects air force ) or ( road projects air force ))) or ( a project based force ))*.