Mongodb query for selected data

@ScottF
Sorry I am not able to write projection for it,

my situation is like i am writing query:{“MBLNR” : {$exists: true, $ne: “”}},
it means if any field name MBLNR is there in “mseg” table, bring all data for this table…
when data comes it is in huge volume,

So i need to reduce this large data coming…