Classification Export when number of keys are small (<5K)

Hi,

I am trying to use Classification Importer to update a new mapping as a subclassification to a child classification of an evar 
To get that, I am first trying to get a template of the format : 

I am not aware of all key values for the evar so trying FTP export which usually takes a long time.

Now, although the evar (key values column) is low_traffic_evar, I only need a subset of the evar values that have a specific format. 
Q. Instead of FTP export of classification to get all key values, can I just filter for the subset key values in Omniture workspace and download the filtered values directly (using Download Items as CSV feature) would that cover all the required keys I am looking for?