The full conjugation of the verb 'bod' = 'to be' is given in the notes for this unit.
'Mae e' is the statement 'He is/He does'
'Dydy e' is the negative 'He is not/He does not'
Therefore:- 'Mae e eisiau' = 'He is wanting (He wants)'
'Dydy e ddim eisiau' = 'He is not wanting/He does not want'