Categorize knowledgebase articles (powered by PHP HESK script) by catalog number or multiple catalog numbers

We have a product help desk/knowledgebase powered by HESK in PHP. For each article, we have assigned a catalog number of the product the article pertains to (it did not have this feature out of the default package). However we would like a freelancer to do the following: 1. Allow the ability to have an article tied to multiple catalog numbers using a single database field and separating each catalog number by a comma. 2. Allow the ability to click the catalog number tied to the article to bring up a page with all articles relevant to that catalog number. 3. Allow the ability to search the knowledgebase questions on the main knowledgebase section together with a catalog number. Disregard dashes or symbols in the catalog number. If the keyword box is empty and just the catalog number is entered, then it will just return a page with all articles relevant to that catalog number.