If you only want to export results for one specific Pulse Survey or Flexible Survey, go to your Admin View and click on the Share tab on the left sidebar.
To export all of your Pulse Survey data, go to the Downloads page in the Share tab and click on the top right corner where Export All is located. Then select Pulse Stats and Responses to have all historical Pulse Survey results downloaded as an Excel file.
If you only want to export results for one specific survey, go to the All Surveys page in the Share tab and click on the Create Report button to the right of the survey. Or, open up the survey you would like to export in the Surveys -> Engage -> Responses page. In the Responses view of the survey, there will be an Export button in the top right corner of every tab.