Perhaps you should try some spelling variations:
"political terrorism" » "biological terrorism"
"political theorists" » "political theories", "political theory", "political aphorisms", "political theoriess", "political theorys", "political thoughts"
"political theorist" » "political theories", "political theory", "political thought"
"critical theorist" » "critical theories", "critical theory", "critical thrust"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((((("political theorist") OR ("critical theorist"))) OR ("political terrorism"))) OR ("political theorists")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"political theorist\") OR (\"critical theorist\"))) or (\"political terrorism\"))) or (\"political theorists\"))".
• Removing quotes may allow a broader search: (((((( political theorist ) OR ( critical theorist ))) or ( political terrorism ))) or ( political theorists )).
• Adding a wildcard symbol may retrieve word variants: (((((("political theorist") OR ("critical theorist"))) or ("political terrorism"))) or ("political theorists"))*.