Keyword Research - 1 Search Term
I have an awesome (expensive, now unavailable due to licensing restrictions) program that does all sorts of searches to help you determine what keywords to use on places like Etsy, Amazon, Google and Bing., Google Market, eBay and YouTube.
This Simbi service is for one search using whatever term you'd like - I'll provide you with a spreadsheet of results. You can use all, some or just one of the aforementioned search places.
Example: I put in "breakup", and chose only Etsy and Amazon. The higher (ie 1) rankings mean there's a lot of searches for this term, but very few results. Shockingly, I discovered lots of 1's for variations of "breakup journal" and "breakup coloring book". When I looked on Etsy and Amazon, I only found 4 offers between the two sites that had anything relevant. Yet, my keyword program tells me they're searched for often.
I suggest general over specific, but it's really up to you. General will get you more hits, but they might not be as targeted as you want.
Training & Qualifications
I've written professionally online for over two decades and use this software daily to help me decide on keywords for my work.
Availability & Preferences
Varies. I'm flexible, and try to check Simbi regularly.