Yes, HighTower is correct, you need to enable Application Metering. Currently, we use a wildcard and meter all applications so that we absolutley have the data because like HighTower said you can only pull data once you start metering it. Once you enable it, you can use this SQL querey I wrote to pull the data. Just replace "Photoshop" with the name of the exe you are looking to discover...
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SELECT
vc.[Name] AS Computer_Name,
vc.[User] AS Primary_User,
eas.[Start Date] As Launched,
eas.[FilePath] AS Program,
est.[Total Run Time]
FROM
vComputer vc
JOIN Evt_Application_Start eas ON eas._ResourceGuid = vc.Guid
LEFT JOIN Evt_Application_Stop est ON eas._id = est._id
WHERE
-- START Date parameter below uses current time MINUS (X) days
eas.[Start Date] > CURRENT_TIMESTAMP-100
AND
-- Put the file EXE in the wild card parameter below
eas.[FilePath] like '%Photoshop%'
ORDER BY
eas.[Start Date] ASC