It just takes doing it day in and day out...and like swimming/musical instruments/lifting weights it gets better over time with each session/practice. Just gotta commit to that 2 hours a day stuff for a stretch. Going back to life studies and focusing on peoples faces or sections of the face for a couple months. Realism isn't half as hard as committing to a certain style of work (lIke manga) So if you can do manga you have the wherewithal for realism too -of this I have no doubt.
But It always comes.
You could do this too - just not right now but with time you could. I have faith that you could do this too if it was really what you wanted to do.
I too am not at a level where I would like to be...but one day. Give me time. ;)
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