possibly

возмо́жно

Perhaps; indicates that the proposition may be true (is not certainly false) regardless of any facts or circumstances known to, stated by or implied by the speaker

• How could Tom possibly know that?

  Откуда Том мог это знать?

  Tatoeba · CK · CC BY 2.0 FR

• How could I have possibly known that?

  Откуда я мог это знать?

  Tatoeba · CK · CC BY 2.0 FR

возмо́жно

In the realm of possibility; indicates that the action may successfully be performed (is not impossible) regardless of any facts or circumstances known to, stated by or implied by the speaker that might limit the performance