I am having some issues trimming the hair on my Shih Tzu. Everywhere I look and read, all the groomers say to trim with the grain of the hair, however, this is proving impossible, for some reason. I'm using a #1 guard with a 30 blade and I can't hardly seem to get any hair to come off, unless I go against the grain, which, of course, leaves lines. When I do catch patches, it gaps him. Especially for the really fine hair on his legs, the razor has no effect and when it does, it leaves gaps. I have tried multiple angles, speeds and pressure. It's like the hair just goes under the guard or it gets pushed out of the way. I am using an Andis AGC and the blade is brand new. Can anyone offer any advise?