The bathroom sink, the water is draining very slowly but the shower and toilet is fine .I took off all the plumbing all the way to the main of the sink I see no blockage what di I do to have the sink draining properly . Please Help.

Did you remove pop-up plug and clean it ? Milo

Follow Milos advice and check the pop up lever to see if any hair is blocking the flow. If that's cleat then You have a partial blockage in the horizontal Line in the wall. The solution would be to remove the "J" bend from the trap (see image) and sen a snake up into the wall. Put out at least 6 foot. Reassemble and test. Better now? Good luck, Tom