I don't think you can do that automatically with /filter. However, if you can make the lines you don't want searched to have some form of identifying character(s), you can exclude those.... (I assume this is from /hsave data).
Example:
All items start with "item_". You can easily remove that from the item name if you need to display the item name later. Then, you can use the -x switch to exclude all lines with item_* in them. Then, you search the other lines for whatever you need. It would end up being two filters, but I'm not sure if there is a better option. Someone else can prove me wrong... I like learning new things.
