Ford Mondeo steering wander car wanders on acceleration

This could be a few thing's,from,front wheel alignment (tracking)to worn steering joints,or bushes,or susension problem,or a bad tyre even,good luck.

It is quite likely to be ur front wishbone bushes it is not an expensive job, normally replace the wishbones,make sure the N/S?F bolt is in the right way round,, if they have been done recentlyit is quite possibly been put in the wrong way round and it knocks the bush out very quickly.