I want to get in googleappsapi the results of trueview ad

[anonymous]

How do you do?

I want to get in googleappsapi the results of trueview ad

The following sample code

function myFunction() {
  //notasecret
ss = SpreadsheetApp.openById("xxxxxxxxxxx");


sheet = ss.getSheetByName("sheet1");
var cell = sheet.getRange(1,1);
var ga = Analytics.Data.Ga.get("ga:xxxxx",
"2015-01-01",
"2015-01-31",
"ga:costPerConversion,ga:impressions,ga:isTrueViewVideoAd");
for(var k = 0; k < ga.getColumnHeaders().length; k++) {
cell.offset(0, k).setValue( ga.getRows()[0][k] );
}
}

Error:Unknown metric(s): ga:isTrueViewVideoAd

trueview advertising of CV, Impression, and I can get cost will be how?