Instituto para la
Investigación Educativa
y el Desarrollo Pedagógico

Perhaps you should try some spelling variations:
"head of state" » "head of hate", "head of late", "head of shame", "had of state", "mead of state", "lead of state"
"read of state" » "read of hate", "read of late", "read of shame", "triad of state"
"heads of state" » "heads of hate", "heads of late", "heads of shame", "means of state", "years of state", "hads of state", "meads of state", "leads of state"
"head or state" » "had or state", "mead or state", "lead or state"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((((("head of state") OR ("read of state"))) OR ("head or state"))) OR ("heads of state"))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"head of state\") OR (\"read of state\"))) OR (\"head or state\"))) OR (\"heads of state\"))".
• Removing quotes may allow a broader search: (((((( head of state ) OR ( read of state ))) OR ( head or state ))) OR ( heads of state )).
• Adding a wildcard symbol may retrieve word variants: (((((("head of state") OR ("read of state"))) OR ("head or state"))) OR ("heads of state"))*.