import re
txt = 'Chevy is my car and Rusty is my horse.\nMy car is very pretty my dog is red.'
print(re.findall(r'(?:\S+[ \t]+){0,2}my car', txt, re.I))
aW1wb3J0IHJlCnR4dCAgPSAnQ2hldnkgaXMgbXkgY2FyIGFuZCBSdXN0eSBpcyBteSBob3JzZS5cbk15IGNhciBpcyB2ZXJ5IHByZXR0eSBteSBkb2cgaXMgcmVkLicKcHJpbnQocmUuZmluZGFsbChyJyg/OlxTK1sgXHRdKyl7MCwyfW15IGNhcicsIHR4dCwgcmUuSSkp