Dunno what web tools exist for this, but you can make a websocket request like so and search your notes for certain keywords:
`["REQ","l",{"kinds":[1],"authors":["d7536260b88cf7e5cc3fca4f82240f342bc098762cf3b855d5d765e78c95ddcb"],"keywords":["nostr"]}]`

This example has your public key already filled in, just replace "nostr" with the word you are searching for and comma separate multiple values.