drilling steel

Hi, I recently purchased some HSS steel bits to drill three holes into a kitchen column so that I can put a TV stand onto the wall. This is the TV stand: Ibra Flat TV Mount This is the TV: Samsung 32 Inch After drilling smaller pilot holes (Slow with WD40) into the wall I found that it was...

im trying to put up some curtain brackets but the window lintel has steel inside - ive have tried using hss drill bits but have failed - they get blunt and super hot can anyone advise on how i can drill into the steel lintel - thanks