If you haven’t already, I personally recommend using www.wordreference.com for your English-Spanish or Spanish-English dictionary needs. If there is a word or even a colloquial phrase that you’d like to have translated, it may be in the dictionary section. However, if you can’t find it there, don’t fret! Word Reference’s forums may have the phrase you’re looking for, and if it doesn’t you can leave a post and a Spanish or English speaker can help you out.
Happy learning!