Question: Problem with subscripts

I need to use subscripts to define a system of equation and its respective variables. I do not encounter any problem when I use solve or Basis (with Groebner package) but when I tried to use RealRootCounting (with RegularChains and SemiAlgebraicSetTools packages), I got the following error message:

Error, (in RegularChains:-SemiAlgebraicSetTools:-RealRootCounting) invalid input: TRDnearsolve expects its 5th argument, vlist, to be of type list(symbol), but received [p[1], x[1], q[1], u[1]]

Clearly [p[1],x[1],q[1],u[1]] is a list but the type of p[1] is indexed and not symbol, this is my guess of what is going wrong.

Now is there any easy-work around this? I looked for similar questions here, tried to use the command convert but so far no luck. :-(