fn_dblog not showing up deleted table data
From Thomas LaRock at http://logicalread.solarwinds.com/sql-server-dbcc-log-command-tl01/#.VXbj_DYpDVk

"The fn_dblog() function (formerly known as the DBCC command) is one of several undocumented functions for SQL Server; it allows you to view the transaction log records in the active part of the transaction log file for the current database."

The fact that you can no longer find your data suggests that the desired part of the log is no longer in the active part of the transaction log file.

One way to get these 4 rows back would be to restore a copy of the database to a temporary database name (e.g. DbName_Disaster) at a point in time that contained these 4 rows. Then insert the 4 rows back into your production database and drop the DbName_Disaster database.

Or you could look for some database recovery tool that fits your need.  The prices and features vary.