Perhaps you should try some spelling variations:
"quantum physical" » "quantum classical", "quantum critical", "quantum logical"
"quantum chemical" » "quantum mechanical", "quantum chemistry"
"quantum optical" » "quantum optics"

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: (((((("quantum physical") OR ("quantum chemical"))) OR ("quantum optical"))) OR ("quantum physics")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"quantum physical\") OR (\"quantum chemical\"))) or (\"quantum optical\"))) or (\"quantum physics\"))".
• Removing quotes may allow a broader search: (((((( quantum physical ) OR ( quantum chemical ))) or ( quantum optical ))) or ( quantum physics )).
• Adding a wildcard symbol may retrieve word variants: (((((("quantum physical") OR ("quantum chemical"))) or ("quantum optical"))) or ("quantum physics"))*.