$re = '/^(?=.*(\d{4}))(?=.*\b(Canada|Malaysia|France|South Africa)\b)/m';
$str = 'This is just the title and has no year or country:
Preamble with only year 1999 and no country:
I was born in 1990 in Canada, I was born to love, and be loved.
She was born in 2000 in Malaysia and she likes fishing.
My mother was born in South Africa and she love all her sons and daughters, she was born in 1960.
My Dad was born in a small village in France in 1955. He loves my Mom.
and finally thanks from USA, without a year.
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php