Hi, my 1st urinanalysis result indicated a '5 cells/ul' under 'ur rbc'. 2nd test report provided only 'dysmorphic and isomorphic rbcs' as '0'. Why?

Difficult. If the urine chemical strip tests positive for blood, the dysmorphic red cells may have spent time in the renal tubules, suggesting significant kidney disease. If there are only a few cells (as in your first case), and your doctor agrees, follow up in a few months.
Blood cells in urine. In my opinion, a finding of 5 red blood cells or less in urine is not a significant finding. Therefore it would not matter how the shapes were described. You should feel good that there are zero abnormally shaped (dysmorphic) cells. Isomorphic means "all in the same shape and size".