Hello Ganesh,
you can simply invite them via the access management. What they cannot do, is browse to the space, because they do not have access to the parent folders. But in the Mail oder Workflow Task or via manual message from you, you can supply a link to the space in question, which they can follow. And if this is a more permanent access, it makes sense for the "others" to create a shortcut link to the space in their own homespace.
This way, they can browse to their homespace and follow the link to you space from there.
Regards, Norgan