How to make N samples distributed over M threads where N >= M in jmeter

I have a test scenario where I have a Main.csv file that contains data as

Main.csv
    one.csv
    two.csv

and inside one.cvs i have data like

one.csv
   one_one
   one_two
   one_three
   .
   .
   so on
two.csv
   two_one
   two_two
   two_three
   ....so on

Now i am using CSV data set config to read contents of main.csv and using loop controller to loop through one.csv to read contents using __csvRead() function and similarly for two.csv

I am unable to execute contents inside one.csv in concurrent manner i.e if i have 10 lines in one.csv, one thread is picking up all the values of one.csv and executing 10calls in sequential manner which i want some 5 threads to distribute among them selves and execute in a concurrent manner. Is it possible?