After ripping out my carpets and the wood nailed to the slab there are many holes (most not too deep) in the cement. Should I fill these holes with some type of floor leveling compound prior to installation? Maybe it really doesn't matter? Thanks!

Last week we had our red oak hardwood floors refinished (sanded down and sealed). They look much better than they did, but when the workers applied the coats of sealant to the floors, they sealed in dozens and dozens of dog hairs. I would estimate that in the ~1,000 sq ft of flooring we had refinished, that there are about 100 dog hairs trapped under the sealant layers. We talked to the company that perofrmed the work and they said to use a razor blade to cut into the sealant enough to grab the dog hair and then just pull it out. Over time, walking on the floors will wear down the little ridge that was left in the sealant layer where the hair used to be. This is the first time I have ever refinished hardwood floors, so I'm not sure if this is typical/normal - can anyone who has had their hardwood floors refinished weigh in on this for me? We paid about $2,700 to have the floors refinished and to be honest, I'm pretty disappointed with all the visible dog hairs. They are going to drive me crazy over time when I'm cleaning and trying to dustmop/vacuum up a hair I can see, but won't be able to get because it is trapped under layers of sealant. Any suggestions? The company that performed the refinishing seems to be done with us - they came back and said they got some of the more visible hairs, but I think they just took off some of the post it notes that we had on the floors pointing to hairs up...there are still so many left. Am I being too picky? Is this normal for a refinish job? Here are two pictures of examples - one of a larger hair and one of a smaller that is sealed into the floor: [ATTACH]48754[/ATTACH] [ATTACH]48753[/ATTACH] Thanks in advance.