...if I may?

I have been asked if I would tutor a young lad with 'Word Finding Difficulties' to help him pass his English GCSE.  He is absolutely brilliant in mathematics and music, has an artist's talents and has perfect hand eye co-ordination judging by his juggling abilities.  He has already passed his 'A' levels in Maths and Music at 17.  He needs to get to Uni and has chosen Kings in London but he cannot get in without his English.

Does anybody have any advice to give me on this 'Word Finding' problem?  It's not part of the Dyslexia syndrome, nor is it related to Aspergers or Autism.  If you showed him a picture of a swan, he would say it was a duck, so he can relate and he knows it's wrong even as he says it.  If you ask him to name 10 foods, he will name a group i.e. meat, veg, salad - he will not name them individually - if you see what I mean?

I have looked it up in fairly authoratative journals but whilst they explain the reasons behind it, they're not big on supplying teaching methods.  He has been assessed recently, as the school unfortunately, don't recognise the syndrome.  I'm specifically looking for methods of getting him to remember words, even though he is not actually short of vocabulary at all.  It's difficult and I thought maybe someone out there would be able to help or at least point me in the right direction.

So, all advice gratefully received.  Many thanks for reading.