import re
text_list = ['Industry / Gemany / PN M564839', 'Industry / France / PN: 575-439', 'Telecom / Gemany / P/N 26-59-29', 'Mobile / France / P/N: 88864839']
regex = r"/ P/?N:? ([\w-]+)"
res = []
for text in text_list: 
	matches = re.search(regex, text)
	if matches:
		res.append(matches.group(1))

print(res)