Find proper “text domain” within theme

Within the code, can you see any syntax like either of the following?

__( 'Hello, dear user!', 'my-text-domain' )

_e( 'Your Ad here', 'my-text-domain' )

That is, strings starting with __ (double underscores) or _e. If so, where the above says my-text-domain, you should find the name of your text domain.