Not familiar with the carb however a quick web search leads me to believe these two brass coloured screws you refer to act actually the carb's fuelling jet assemblies.
One will most probably be the main jet assembly and the other the "air correction" / "emulsifier" assembly.
As such they are not adjustment screws however they can be unscrewed and removed for cleaning.
Just remember to put them back exactly where they came from and if you disassemble the individual components then ensure you do not mix them up.
These components are *crucial* to the correct fuel air ratios for your carb & engine combination and messing with them unless you know what you are doing. By virtue of your question then these are "do not mess with" items