Way to find differential backup for SQL Database

1.Check MSDB backup history for that database

select * from msdb.dbo.backupset where name='dbname' and type='i' order by backup_finish_date desc

2.dbo.backupset: provides information concerning the most-granular details of the backup process
dbo.backupmediafamily: provides metadata for the physical backup files as they relate to backup sets
dbo.backupfile: this system view provides the most-granular information for the physical backup files

USE AdventureWorks
GO
SELECT TOP 100
s.database_name,
m.physical_device_name,
CAST(CAST(s.backup_size / 1000000 AS INT) AS VARCHAR(14)) + ' ' + 'MB' AS bkSize,
CAST(DATEDIFF(second, s.backup_start_date,
s.backup_finish_date) AS VARCHAR(4)) + ' ' + 'Seconds' TimeTaken,
s.backup_start_date,
CAST(s.first_lsn AS VARCHAR(50)) AS first_lsn,
CAST(s.last_lsn AS VARCHAR(50)) AS last_lsn,
CASE s.[type]
WHEN 'D' THEN 'Full'
WHEN 'I' THEN 'Differential'
WHEN 'L' THEN 'Transaction Log'
END AS BackupType,
s.server_name,
s.recovery_model
FROM msdb.dbo.backupset s
INNER JOIN msdb.dbo.backupmediafamily m ON s.media_set_id = m.media_set_id
WHERE s.database_name = DB_NAME() -- Remove this line for all the database
ORDER BY backup_start_date DESC, backup_finish_date
GO