Fuzzy Search for filenames with synonyms and tags (auto generated)

Filesystem: Ext4 I create separate files for each topic. I have thousands of files segregated into 2 or 3 levels of hierarchical broad categories. I would like to search for these files efficiently. > For example, if I have a file Finance.md (not limited to markdown, e.g. Finance.tsv, Finance.txt, Finance.html, Finance.pdf), I would like following sample of tags to represent this file: > > loan, money, bank, investment, credit card, tax, Steuer (German word for Tax), tAX, Tax1 So, if I search with a particular tag, it shows all filenames that are represented by the tag. How can I do this? Moreover is there a software which could auto generate this tag for each file, and store it as a list that can be inspected and edited for future use? Also, may be when a new file is being created it would point that similar files based on the tags already exist. Would be nice to restrict this function within a particular parent directory and not the entire file system. If its not possible on ext4, I am open to virtual file system that could be enabled for a particular folder inside EXT4 filesystem. Also, I would prefer an opensource CLI tool, but GUI tools are also welcome.