Moved to DLP for better support.
There is different levels of signature generation. What you are describing is low granularity. Low granularity only provides 1 signature for the document meaning any change will alter the signature. Try removing the registered documents and re-registering them with medium granularity.
More detailed info can be found in KB73218.
Hi, Pinaki Bhadra!
Try to config you registration rule that:
Do Shedule with smallest time between the two scans (e.g., 1 in every 5 minutes or once every 1 hour). It depends on how often you add new files to the network storage or database.
Choose Signature Type High Granularity.
You can reed about Signature type in "Table 14-18 Definitions of signature types" at page 199 into "Product Guide Revision B McAfee Data Loss Prevention 9.3.2" (ndlp_932_pg_b_en-us.pdf).