@ayman_h  - I think it depends on your intents and your end user access. I believe the recommendation is 1 Model per entry point (if you have a single portal, use a single model). What are your 3 intents in each of the 3 models? 
Without knowing your intents and matching topics, it's hard to make a suggestion. 
One item to consider might be how you are using tables as vocabulary sources and entity mapping in an intent. 
Another consideration is specific to "I need..." is that an intent for the catalog? There might be a better way to do catalog requests. The recommended approach for catalog requests and KB articles is to allow fallback search activities to catch that query v building topics around accessing the catalog. Are you using AI Search? 
If you're using AI Search as your fallback, it might be better to let the search return the result v trying to build a conversation around all the utterances users might present in a topic. 
A couple of ideas - if you have more specific details to share, I'll watch for updates.