import re
reg = r"\b\d{1,2}([./-])\d{1,2}\1(?:\d{4}|\d{2})\b"
s = "01.11.11 12/12/1981 1*51*12 . 22|1|13 03-02-1919 1-22-12 or 01-23-18 or 03-23-1984 01.11.18 or 2.2.17 or 02.02.18 or 12.1.16 12.23.1943 01-23-11 not 12.23.192 not 02.02.1"

matches = re.finditer(reg, s)
for matchNum, match in enumerate(matches, start=1):
    print(match.group())