can't get docFreq of phrase

[SK R]

Hi,
   I can get docFreq. of single term like (f1:test) by using
indexReader.docFreq(new Term("f1","test")). But can't get docFreq. of phrase
term like f2:"test under") by the same method.

   Is  anything wrong in this code?
   Please help me to resolve this problem.


Thanks & Regards
RSK