You may start with one search term only, however it is an excellent idea to combine your search term with others. These may be terms that you come across while you are doing the initial search, or they may just be things that you want to try out. So, instead of searching just for "imagination" as a single term (as Misia is doing), it may give wonderful results that may really broaden her horizons if she combines "imagination" with let us say, "philosophy" "creativity" "science" "curiosity" and many others. Below, I am going to use Misia's search on "imagination" as an example, however this applies to all such searches. Simply substitute your own search term with "imagination" and find other terms that you think relate to it. (And, some of the ones that I listed above, may well apply to an extension of your query as much as they do to the term "imagination," therefore, by all means, use those also).

So anyway, I became curious myself, and coupled the terms "imagination" and "curiosity" in a simple google search:
https://www.google.com.tr/search?q=imagination+and+curiosity&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb&gfe_rd=cr&ei=aLAyVNakEeLc8ge23IGICw
Which led me to this very cool text - and incidentally this is the first result, so I didn't even have to look very far:

All of your topics will lend themselves to such combinations. And these combinations need not be related to one another - indeed the less related they seem to be, the more interesting will they be in terms of outcome. Oppositions, contradictions, synonyms, antonyms - you should be quite courageous in what you put together. And as I said above, it is good to always bear in mind that sometimes the second terms may also come out of the initial search for just the one term. So, be on the lookout for those also:

We can see how such secondary terms come out of a primary search when we look at the search results for the term "imagination" all by itself, the wikipedia link for it (http://en.wikipedia.org/wiki/Imagination) talks about "story-telling" right at the start. And also has a link to the term "story-telling." (Which you should be looking at, of course, since the page gives you a direct link). But what happens when we combine "imagination" and "story-telling" is this:
Where we find this, just a little bit down:
Which is actually based upon a TED talk. (So, I would search for that also, of course). But what happens now is that we have this link that suddenly gives us a completely new (and fascinating!) term - namely "fear" that the author is coupling with "imagination" and "story-telling." A triple combination which, I would suggest, will open entirely new vistas of thought for a creative practitioner since it is actually bringing together terms that may not be immediately related to one another... Which can then be combined with other stuff and other stuff and other stuff - until you reach an idea / viewpoint / discussion that you can expand upon and make your very own - as a text, but especially as the conceptual framework or content for new/enhanced creative output.
:-)