Search for only one word

[bebijuteria]

I am creating a search by color in my website.
But i have some products, that are "Blue" and others "Dark Blue".

I want to separate them, when i seach by blue i don't want to show the dark blue. But i can use " " in the url.

[bebijuteria]

And i would like to make some news url, like this:

Silver + Gold -> That search me silver ones and gold ones.

Can anyone help me