What can be done for manboobs?

Unlikely to happen. The age listed on your profile is 36. If true, this is long past the age when puberty related gynecomastia will fade. Getting your body fat content below 20% can help since weight can aggravate the issue. I would see your doc and make sure you do not have a treatable condition that brought this about. If not a consultation with a plastic surgeon with experience in the area would be my next move.
Manboobs. A plastic surgeon should be consulted to see if reduction mammoplasty would be effective.