Hi Santosh,
I suggest you to follow-up them by talking to them ,you can use our community message service or messenger to initiate the conversation. I feel make them friends and tell them all benefits that they are currently missing from not being active. Ask them if they have any query solve them, or ask them to post those queries on forums.
But remember don't force them to post on boddunan, you can motivate them.
-Atul Barapatre
Note: You have asked all your queries in wrong forum section, Please follow the forum guidelines. Post them under proper section. You would have posted this query in help section.
Please take from next time.