Perhaps you should try some spelling variations:
"comercio del marketing." » "comercio de marketing.", "comercio e marketing.", "comercio y marketing.", "comercio dde marketing.", "comercio dy marketing."
"comercio en marketing." » "comercio de marketing.", "comercio y marketing.", "comercio _ marketing.", "comercial en marketing."
"comercio el marketing." » "comercio de marketing.", "comercio y marketing.", "comercio e marketing."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("comercio en marketing.") or ("comercio del marketing."))) or ("comercio el marketing."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("comercio en marketing.") OR ("comercio del marketing."))) OR ("comercio el marketing.")).
• Removing quotes may allow a broader search: (((( comercio en marketing. ) or ( comercio del marketing. ))) or ( comercio el marketing. )).
• Adding a wildcard symbol may retrieve word variants: (((("comercio en marketing.") or ("comercio del marketing."))) or ("comercio el marketing."))*.