An important part of researching is formulating your search strategy and revising it as you go. A search for academic material can take several tries to obtain a complete picture or enough sources to satisfy your needs. From your description you have the following concepts:
strategic planning
operational planning
business
Can you think of other terms for these concepts? For business you could also use terms like firms, company, corporations. If you are thinking of a small business , then try the term "small business" or "small enterprise".
Here's a possible search strategy
(business OR firm OR company OR corporation) ('strategic planning" OR "operational planning") "best practices"
[I added this phrase "best practices" to the search to focus on more general articles, but you can try with or without].
Try this search in Discovery and our main search tool found on the Royal Roads Library homepage at http://library.royalroads.ca/ and Google Scholar .
Once on the results page of Discovery or Google Scholar, refine the results with the options available to you in the left sidebar. Click off peer-reviewed and you may want to adjust the date of publication.