Without looking at the response I'm guessing you might be seeing multiple matching variations from the same listing. You can eliminate those by using the ItemFilter HideDuplicateItems and setting it to true. This will collapse all variations into a single listing which only has the lowest price.
`findItemsByKeywords` returns duplicates when the item has variations. Like item ##### has a red/green/blue option a buyer can chose - 4 hits a return, one for the listing itself and one for each option/variation.