There exists a huge number of amino-acids, most of them are not made or used by the known living beings and of those made by living beings even fewer are used in proteins.
A very large number of random amino-acids have also been found in various meteorites, because they easily form from the most abundant chemical elements in the Universe, H, C, N and O, whenever there is not enough oxygen to oxidize everything else, but among them only about 10 of those used by living beings have been found, i.e. about one half of the amino-acids used in proteins.
What would have been interesting to know about the Japanese asteroid probe would have been if, among the many amino-acids found, there have been also the same about 10 amino-acids previously found, or only a part of them, and if there has been found any other amino-acid with biological importance besides those ten.
The press release mentions only glutamic acid and valine, 2 simple amino-acids which belong to those 10 about which it is well known that they can easily be synthesized in abiotic conditions.