Perhaps you should try some spelling variations:
"call actions research : july 2007" » "call action research : july 2007", "call actional research : july 2007", "call actors research : july 2007", "small actions research : july 2007", "call options research : july 2007", "call auction research : july 2007", "call actions research : july 2008", "call actions research : july 2013", "call actions research : july 2012"
"call operations research : july 2007" » "rail operations research : july 2007", "chain operations research : july 2007", "cargo operations research : july 2007", "call operations research : july 2008", "call operations research : july 2013", "call operations research : july 2012"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("call actions research : july 2007") or ("call operations research : july 2007"))~.
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