Perhaps you should try some spelling variations:
"multiple imputations research : july 2009" » "multiple imputation research : july 2009", "multiple implications research : july 2009", "multiple mutation research : july 2009", "multiple reputation research : july 2009", "multiple imputations research : july 2008", "multiple imputations research : july 2007", "multiple imputations research : july 2019"
"multiple options research : july 2013" » "multiple locations research : july 2013", "multiple positions research : july 2013", "multiple solutions research : july 2013", "multiple actions research : july 2013", "multiple optics research : july 2013", "multiple operations research : july 2013"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple imputations research : july 2009") or ("multiple options research : july 2013"))~.
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