Did you tried creating a formula field and applying that to report as a filter criteria for those specific report. With this method, even though the reports are exposed to users, when they run, they dont see that data being populated. I often do this to place additional control on who can view the data in reports.
Example: Formula Text field
1) create formula text field in the table : "View Allowed-My Boss" = If ( User()=ToUser([My Boss email address]) , "Yes","No") And <other data conditions> to filter out the data.
2) Customize the report you and add data filter on top of you existing crieria's using View Allowed-My Boss = Yes
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Babi Panjikar
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