How can I put my bus pass on I phone when it is not in the search

You'll have the option to add a Credit Card, Debit Card, Apple Card, or transit card in certain cities, so that depends on your country.

For example: add Debit Card or Public transport card.

Debit Card -> Choose a bank, tap on your Bank and add.

Public transport card ->  only some countries can be added, tap on it and see if your country is listed.

I can't add my public transport ticket to Wallet yet.