A blue lazy flame is actually what you want! This means that the fuel air mixture is correct. The flame of natural gas (mostly methane) burns blue because it contains more hydrogen atoms than carbon atoms which makes the fuel burn cleaner. A yellow flame is indicative of not enough oxygen and incomplete combustion and a blowing, noisy blue flame is indicative of too much air causing a draft and a blowing sound. When you blow at the air intake, you are introducing molecules of water and carbon dioxide which interferes with combustion. Look at the flame on your gas range. It should be blue and steady!

I have a gas stove with a log set and when the unit first turns on, the flames are blue, nearly invisible and very lazy, but when the logs heat up to cherry red the flames turn yellow. Do a little experiment. Hold a nail (with a pliers of course) in the flame of one of your gas range burners. While the nail is cool it will just be a blue flame, but as the nail becomes red hot the flame will become yellow. That's the same idea with gas logs. if your flame isn't turning yellow, it probably means you are not getting any flame contact with the logs. I'm not familiar with your log set but I would try to arrange them so that they are in direct contact with the flames, but just make sure you allow enough time for them to heat up sufficiently to produce a yellow flame. Let us now if this helped.
Jim