Confusion between clamscan and clamdscan

If i am running clamscan -v under clamav-0.99.1 package, it is showing

----------- SCAN SUMMARY -----------
Known viruses: 4297948
Engine version: 0.99.1
Scanned directories: 1
Scanned files: 39
Infected files: 0
Data scanned: 5.25 MB
Data read: 2.37 MB (ratio 2.22:1)
Time: 6.649 sec (0 m 6 s)

If i am running clamdscan -v under clamav-0.99.1 package, it is showing

----------- SCAN SUMMARY -----------
Infected files: 52
Time: 1.936 sec (0 m 1 s)

If i run particularly under clamav-0.99.1/test directory, clamscan -v, it is showing

----------- SCAN SUMMARY -----------
Known viruses: 4297948
Engine version: 0.99.1
Scanned directories: 1
Scanned files: 52
Infected files: 48
Data scanned: 14.52 MB
Data read: 6.94 MB (ratio 2.09:1)
Time: 8.117 sec (0 m 8 s)

And in clamdscan -v, it is showing

----------- SCAN SUMMARY -----------
Infected files: 52
Time: 1.184 sec (0 m 1 s)

Why is this difference?? Does running from super directory and particular directory matters??

Why clamscan -v is showing

Scanned files: 52
Infected files: 48

while clamdscan -v always showing

Infected files: 52

??

clamdscan is configured in /etc/clamav/clamd.conf. It allows faster scan by using parallelization with --multiscan which is using more resources, of course.