cat, drooling and falling over

Please help. I took in a cat who had been injured? she was severely dehydrated and couldn't support herself on her hind legs , she was also very very skinny. She spent 4 days at the vets on a drip and then, for the past week has been eating and drinking small amounts and walking round but still keeps falling over. For the last 2 days she hasn't eaten are drunk at all and today she was drooling and brought up yellow fluid (bile?). I don't have much money and the vets here don't have the equipment etc to help very much. Thank you

SHE'S VERY SICK. YOU DON'T KNOW WHY. DO NOT ASSUME THAT VETS DON'T HAVE "THE EQUIPMENT" TO HELP A CAT.
   
A vet has to see your cat.
   
She may have had a stroke.

Thanks for your reply. Only the big towns have xray machines etc and facilities for in depth diagnosis. I did take Phoebe to another vet, a young couple who diagned a kidney infection - they were brilliant and as it turns out, correct. They checked out the symptoms with their university lecturer and the treatment they had given her was confirmed and they continued treating her at the surgery. However, bless her, she just wasn't strong enough and died yeaterday morning. The first vet didn't pick it up and just treated her for dehydration. I get so upset and just don't know who to trust. I spend a lot of money on the sick stray animals which I guess I don't mind if I know they are diagned and treated properly. Thank you for taking the time to respond and best wishes to you