sisu should translate to "determination / strength" in English
This is a Finnish researcher who explains the concept - it's different from determination, strength, or resilience, though they touch on it https://youtu.be/UTIizGyf5kU
Searching for = looking for ...same thing cmon!!
"Tyyne seeks" should be an alternative translation.
I thought that Tyyne was a male name.
My late wife had an Aunty Tyyni, so definitely female. Gender of Finnish names isn't obvious to Indo-europeans, e.g. she also had a male cousin called Aimo (son of Tyyni), but, as we have learned here, Aino is a female name.