When I run the man command in Linux. It returns manual for some packages, but in some case it says
no manual entry for <package_name>
for-example: man cloud-guest-utils command or man btrfs-tools and some more also.
Is there no manual available for these packages or is there some else issue?
It means that there is simply no manual available for the requested command. You will get the same error if you try man any-string.
You may use tab-completion if you are not sure about the man entry name; the tab-completion is usually enabled in the latest distribution.