Perhaps you should try some spelling variations:
"lucha una investigacion" » "lucha la investigacion", "lucha e investigacion", "lucha ciencia investigacion", "lucha en investigacion", "hacha una investigacion", "luna una investigacion"
"lucan ma investigacion" » "lucan la investigacion", "lucan a investigacion", "lucan iap investigacion", "lucas ma investigacion", "lujan ma investigacion", "lacan ma investigacion"
"juan de investigacion" » "juan la investigacion"

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: (((("lucan ma investigacion") or ("lucha una investigacion"))) or ("juan de investigacion"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("lucan ma investigacion") OR ("lucha una investigacion"))) OR ("juan de investigacion")).
• Removing quotes may allow a broader search: (((( lucan ma investigacion ) or ( lucha una investigacion ))) or ( juan de investigacion )).
• Adding a wildcard symbol may retrieve word variants: (((("lucan ma investigacion") or ("lucha una investigacion"))) or ("juan de investigacion"))*.