老老实实地找呗
char buff[30]=......;
char buff2[30];
int i=0,j=0,flag=0;
while(buff[i]!='\0')
{
  if(buff[i]=='\"')(flag=!flag)||buff[j++]=32;
  else if(flag)buff2[j++]=buff[i];
  i++;
}
buff2[j]='\0';