Get original value from keccak_256 if the original value is small in size (less than 256 bits)

Question

When converting an arbitrary long text to 256 bits, information will be lost. So, it is impossible to get it back. However, if the original text is just few bits long, can we get it back from the keccak_256 hash?

For example:

Original text: a
Keccak_256: 3ac225168df54212a25c1c01fd35bebfea408fdac2e31ddd6f80a4bbf9a5f1cb

Here the original text is just 8 bits but the hash is 256 bits. So, is that information really lost? If not, how do I get it back.