Perhaps you should try some spelling variations:
"cronicas mexicana en medicina interna ;" » "cronica mexicana en medicina interna ;", "cronicas americanas en medicina interna ;", "clinicas mexicanas en medicina interna ;", "cronicas mexicana de medicina interna ;"
"cronicas mexicana la medicina interna ;" » "cronica mexicana la medicina interna ;", "cronicas americanas la medicina interna ;", "clinicas mexicanas la medicina interna ;", "cronicas mexicana a medicina interna ;", "cronicas mexicano la medicina interna ;", "cronicas mexicana una medicina interna ;", "cronicas mexicana de medicina interna ;"

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: (("cronicas mexicana en medicina interna ;") or ("cronicas mexicana la medicina interna ;"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("cronicas mexicana en medicina interna ;") OR ("cronicas mexicana la medicina interna ;")).
• Removing quotes may allow a broader search: (( cronicas mexicana en medicina interna ; ) or ( cronicas mexicana la medicina interna ; )).
• Adding a wildcard symbol may retrieve word variants: (("cronicas mexicana en medicina interna ;") or ("cronicas mexicana la medicina interna ;"))*.