Perhaps you should try some spelling variations:
"serie: balance de investigaciones y" » "serie: balance e investigacion y", "serie: balance la investigacion y", "serie: balance en investigacion y", "serie: balance de investigaciones en", "serie: balance de investigacion e", "serie: balance de investigacion por", "serie: balance la investigaciones y", "serie: alcance de investigaciones y"
"serie: balance de investigacion en" » "serie: balance la investigacion en", "serie: alcance de investigacion en"
"serie: balance de investigacion y" » "serie: balance la investigacion y", "serie: alcance de investigacion y"

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: (((("serie: balance de investigaciones y") or ("serie: balance de investigacion en"))) or ("serie: balance de investigacion y"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("serie: balance de investigaciones y") OR ("serie: balance de investigacion en"))) OR ("serie: balance de investigacion y")).
• Removing quotes may allow a broader search: (((( serie: balance de investigaciones y ) or ( serie: balance de investigacion en ))) or ( serie: balance de investigacion y )).
• Adding a wildcard symbol may retrieve word variants: (((("serie: balance de investigaciones y") or ("serie: balance de investigacion en"))) or ("serie: balance de investigacion y"))*.