regular expression to get ORA- errors out of text

what regular expression would you suggest to get all ORA- errors (with from 1 to 5 numbers)
out of some text like this:

' ORA-00001 ora-0002 ora ora-003 aasdlkja alksdj alksdj laskdj
ORA-04 aaaa a a a aora-5 '

I am trying to figure out how to use
regexp_replace to replace all characters around ora-... errors to get output:

'ORA-00001 ora-0002 ora-003 ORA-04 ora-5'

but can't find appropriate expression so far:

with s1 as (select ' ORA-00001 ora-0002 ora ora-003 aasdlkja alksdj alksdj laskdj ORA-04 aaaa a a a aora-5 ' s from dual) select regexp_replace(s, *'...'*, '...', 1, 0, 'i') from s1 /

-- 
Regards,
Andrey Goryunov

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