They will usually hurry through, not opening closet doors if the owner is there. People will not buy what they can't examine. If you are home when someone comes, go for a walk, or visit your neighbors. You don't know who they are, and it could be very dangerous. Too many dangerous people around nowadays.
Buyers come from many places.
Sometimes they already know the areas that they want to live in, and will drive around the areas that interest them, looking for signs. They'll call their agent, and ask them to check out the property. Your home will be on the Internet, and I send flyers to all the top agents in the area. Sometimes a home will sell quickly if some buyers have been looking for a home like yours for a while. If their agent knows how to take advantage of the Multiple Listing Service, the system will notify that agent that a property matching the requirement of one of their clients is available.