Perhaps you should try some spelling variations:
"otros estudios americanos." » "otros estudios latinoamericanos.", "los estudios americanos.", "etnicos estudios americanos."
"dos estudios americanos." » "dos estudios latinoamericanos.", "los estudios americanos."
"series estudio urbano." » "series estudios urbano.", "serie estudio urbano.", "serie estudios urbano.", "series estudios urbanos.", "series espacio urbano."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("series estudio urbano.") or ((("otros estudios americanos.") OR ("dos estudios americanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("series estudio urbano.") OR ((("otros estudios americanos.") OR ("dos estudios americanos.")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"series estudio urbano.\") or (((\"otros estudios americanos.\") OR (\"dos estudios americanos.\"))))".
• Removing quotes may allow a broader search: (( series estudio urbano. ) or ((( otros estudios americanos. ) OR ( dos estudios americanos. )))).
• Adding a wildcard symbol may retrieve word variants: (("series estudio urbano.") or ((("otros estudios americanos.") OR ("dos estudios americanos."))))*.