Young children's food is unlikely to contain many spices - pepper, ginger, some mild herbs. Salt is often reduced a lot for children's food, so if your childminder is making food from scratch it is unlikely to contain much salt. Older children will be a bit more adventurous but even so many won't try food that looks different, smells different, tastes different.
I think what you may be trying to say is that your child's diet at home is different to that at your childminders. That should be fine, no one wants to be eating the same things every day.
Your childminder needs to prepare food which ALL the children in their care will eat and as you are no doubt aware, children can be rather fussy. Thus the menu may well be designed such that it appeals to all the children, rather than an individual child.
Does your childminder provide a menu, food diary or anything like that so you know what sort of food your child is being offered?
If your child is frequently being sick after eating certain things, is it perhaps an intolerance to an ingredient?