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From my perspective, this may be a very good strategy, and not a problem. It depends why you have 4 landing pages though. I see you linked your site, but I'm instead going to answer more generically, at least in part since I don't read or speak the language of your site. Let's hypothetically say you sell a type of day planner. And you've optimized your product page for the query "day planner". But you know that your day planner is highly relevant to teachers, personal trainers, doctors, and lawyers. You might want 4 very specific landing pages, targeting phrases like "day planners for teachers", with content on those pages which resonates with and helps teachers to understand how your one day planner would be great for their needs. And a separate page for the personal trainers, and for the doctors, and for the lawyers. Your product page might rank best for "day planner", but one of your landing pages might rank best for "day planners for teachers". And I think that's a valid strategy. As opposed to trying to get one page to rank well for all 4 of those audiences, which may also be a valid strategy. I've seen each of those strategies work, in different situations. It very much depends on the competition around your listings, and how they are targeting the audiences (or not), in terms of which is a better strategy (one page with multiple targeted queries, vs 4 pages with individual targeted queries).