In order to dissect which one is more important, we must break down the definition for both:
Amino Acids: we ALL have a combination of the 3 building blocks of protein in our system. The human body depends on these elements to build and maintain the muscular structures in our bodies. There are currently 3 groups of amino Acids: nonessential, essential & conditionally essential. Essential is provided through your diet (ex protein), nonessential is produced by the body, and conditionally amino acids can also by made by the body, but added stress and through injuries the body may not always be able to make them.
Protein (in the form of powders): this type can be available in various sources, with the most common ones being Whey, casein & soy. Lifters and exercise enthusiasts rely on this food sources in order to build and develop muscles in the body, which is essential to take through proper nutrition. Amino are what you call the "building blocks of protein", since without it protein won't be available through plant and animal sources. Vegans and vegetarians understand the importance of "complete protein", as a result they receive their protein through various plant sources.
Essentially, both are important when pertaining to you and your health and wellness goals. Without Protein (which is a by product of amino acids), it'll be hard to maintain a healthy body weight. I suggest to invest in a protein powder that is rich in BCAAs (Branched Chain Amino Acids) which contains the essential amino Acids leucine, isoleucine & valine, in order to build and maintain your muscular structure.