Hi,
By default configuration both the index table and the search input ignores words below 2 chararcters. In your case this is probably an issue, as you want to match them exactly.
I suggest trying this configuration:
1. On the index table options, change the min. word length to 1 – then re-create the index table.
2. On the search instance option, change the min. word length to 1 as well
3. Use the following keyword logic
This should narrow the first set of results to match all the keywords, then the rest.