Perhaps you should try some spelling variations:
"teaching visiting research : july 2011" » "teaching positions research : july 2011", "teaching training research : july 2011", "teaching using research : july 2011", "teaching visiting research : july 2013", "teaching visiting research : july 2012", "teaching visiting research : june 2011"
"mali opinion research : july 2006" » "mali action research : july 2006", "mali options research : july 2006", "mali opinion research : july 2013", "mali opinion research : july 2012"

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