For example in my Car model i have such fields:

```
color, price, year

```

and in form partial i generate form with all this fields. But how to code such logic:

user could enter color and year and i must find with this conditions, user could enter just year or all fields in same time...

And how to write where condition? I could write something like:

```
if params[:color].present?
car = Car.where(color: params[:color])
end

if params[:color].present? && params[:year].present?
car = Car.where(color: params[:color], year: params[:year])
end
and so over....

```

But this is very ugly solution, i'm new to rails, and want to know: how is better to solve my problem?