I'm gonna hijack this conversation as it seems I have a similar issue. Playing SeaBlock with Angel's/Bob's and was trying to look up all "coil" items to show all the items like "Gold sheet coil" or "Iron sheet coil", this didn't work although those are valid items. It seems FNEI is using the internal names not normally available to the user (can be seen in "show-debug-info-in-tooltips" debug setting. The names of the particular items are "angels-roll-gold" and "angels-roll-iron" internally, searching for "roll" instead of "coil" returns the expected results of all the different coils.
Could an option to also search internal names be added?