Perhaps you should try some spelling variations:
"expression chiral" » "expression viral", "expression chairman", "expression chemical"
"expansion chiral" » "expansion central", "expansion chi", "expansion circa"
"expansion direct" » "expansions direct", "expansion dirac", "expression direct"
"expansion data" » "expansion des", "expansion d", "expansion die"
"expansion der" » "expansion des"

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: (((((("expansion chiral") OR ("expression chiral"))) OR ((("expansion data") OR ("expansion der"))))) OR ("expansion direct")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"expansion chiral\") OR (\"expression chiral\"))) or (((\"expansion data\") or (\"expansion der\"))))) or (\"expansion direct\"))".
• Removing quotes may allow a broader search: (((((( expansion chiral ) OR ( expression chiral ))) or ((( expansion data ) or ( expansion der ))))) or ( expansion direct )).
• Adding a wildcard symbol may retrieve word variants: (((((("expansion chiral") OR ("expression chiral"))) or ((("expansion data") or ("expansion der"))))) or ("expansion direct"))*.