Bip39 implementation https://franciscougju442.bravesites.com/entries/general/Produce-Bitcoin-Addresses-from-Seed-Every-Little-Thing-You-Required-to-Know Regardless that it makes use of BIP32 technique you are able to still import BIP39 seeds into Electrum wallet. Also besides BIp32 there is BIP44 Variation which some wallet use for that era of seeds. For words that have only 3 letters... https://kingbookmark.com/story20769089/bip39-vs-not-known-details-about-bip39-word-list-txt-https-linktr-ee-bip39