Perhaps you should try some spelling variations:
"underground workings" » "underground works", "underground openings", "underground mining"
"underground parking" » "underground banking", "underground mining", "underground openings"
"underground parts" » "underground gas", "underground press", "underground karst"

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: (((("underground parking") OR ("underground parts"))) OR ("underground workings")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"underground parking\") OR (\"underground parts\"))) or (\"underground workings\"))".
• Removing quotes may allow a broader search: (((( underground parking ) OR ( underground parts ))) or ( underground workings )).
• Adding a wildcard symbol may retrieve word variants: (((("underground parking") OR ("underground parts"))) or ("underground workings"))*.