Perhaps you should try some spelling variations:
"historical materialism" » "historico materialism", "historicos materialism", "historias materialism", "historical materiales", "historical materializar"
"historia materialism" » "historia materiales", "historia materializar"
"historicas materialism" » "historicas materiales", "historicas materializar", "historicos materialism", "historias materialism", "historico materialism"
"historica materialism" » "historica materiales", "historica materializar"
"historica materializa" » "historica materializar", "historica materializado", "historica materializada"
"historica materializan" » "historica materializarn", "historica materializadon", "historica materializadan", "historica materializar", "historica materializado", "historica materializada"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("historical materialism") OR ("historia materialism"))) or ((("historicas materialism") or ((("historica materialism") or ((("historica materializa") or ("historica materializan"))))))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("historical materialism") OR ("historia materialism"))) OR ((("historicas materialism") OR ((("historica materialism") OR ((("historica materializa") OR ("historica materializan")))))))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"historical materialism\") OR (\"historia materialism\"))) or (((\"historicas materialism\") or (((\"historica materialism\") or (((\"historica materializa\") or (\"historica materializan\"))))))))".
• Removing quotes may allow a broader search: (((( historical materialism ) OR ( historia materialism ))) or ((( historicas materialism ) or ((( historica materialism ) or ((( historica materializa ) or ( historica materializan )))))))).
• Adding a wildcard symbol may retrieve word variants: (((("historical materialism") OR ("historia materialism"))) or ((("historicas materialism") or ((("historica materialism") or ((("historica materializa") or ("historica materializan"))))))))*.