You can go to below location in your machine.
This location will contain separate folder for all the apps you have created (The folder names will be in hexadecimal format). Each app folder will contain a sub folder named "Templates". You should be able to locate your template file there.
Hope this helps.
HI Akash Shah,
By copy pasting this path directly, gave me this folders, if you go searching one by one, folders might be hidden or not visible(which i faced in my working server). So copy paste it directly.
This worked for me, i found my template folders in here, and i distinguised through date modified, in both nprinting 220.127.116.11 and 17.2.0