Your debug log shows that your Pi-Hole is working. This section of your debug log reports the results of testing:
*** [ DIAGNOSING ]: Name resolution (IPv4) using a random blocked domain and a known ad-serving domain
[✓] www.silver-path.com is 0.0.0.0 via localhost (127.0.0.1)
[✓] www.silver-path.com is 0.0.0.0 via Pi-hole (192.168.178.188)
[✓] doubleclick.com is 172.217.18.14 via a remote, public DNS server (8.8.8.8)
It also shosw that over the previous 24 hours, Pi-Hole only received queries from one client (most likely the Pi):
[2019-02-01 09:22:28.106] Imported 166 queries from the long-term database
[2019-02-01 09:22:28.106] -> Total DNS queries: 166
[2019-02-01 09:22:28.106] -> Cached DNS queries: 61
[2019-02-01 09:22:28.106] -> Forwarded DNS queries: 105
[2019-02-01 09:22:28.106] -> Exactly blocked DNS queries: 0
[2019-02-01 09:22:28.106] -> Unknown DNS queries: 0
[2019-02-01 09:22:28.106] -> Unique domains: 13
[2019-02-01 09:22:28.106] -> Unique clients: 1
[2019-02-01 09:22:28.106] -> Known forward destinations: 4
This indicates a network problem with clients finding the Pi-Hole for DNS.
You should only have the Pi-Hole listed as DNS server in order for Pi-Hole to be effective. With a "secondary" DNS server (there is no real concept of "primary" and "secondary", the clients will use any DNS available), clients will bypass Pi-Hole for some or all of their DNS traffic.
The place to start is in your router. Ensure that the Pi has the reserved static IP and that other clients can communicate with the Pi. Some commands that may be helpful:
From a client, run the following commands from the client terminal application. This will check if the client can (1) find the pi.hole on the network, and (2) communicate with the Pi.
nslookup pi.hole
nslookup pi.hole 192.168.178.188
ping -c5 pi.hole
ping -c5 192.168.178.188