Hi Vivek,
So you have vendors in both tables, Is vendor a key field in 2nd table if yes.
Then you can pass vendor from 1st table to 2nd table and fetch data, once you have the data from the 2nd table you need to use do varying just see the sample code below, check that supplier type is not initial
check below link for reference
http://help.sap.com/abapdocu_70/en/ABAPDO_VARYING.htm
hope this helps.