Seeking the equivalent in English for "厚脸皮"
The term is "thick-skinned"


  http://dictionary.cambridge.org/dictionary/english/thick-skinned
  
  Someone who is thick-skinned does not appear to be easily hurt by criticism:


"Thick-skinned" synonym


  http://www.thesaurus.com/browse/thick-skinned
  
  callous : insensitive; indifferent


"Thick-skinned" is the best translation for "厚脸皮". Both can be neutral or  derogatory 

Note: '厚顏無恥' (brazen) - 'Thick-skinned and shameless' is definitely derogatory