Finding the topic for an inquiry can be like fishing - think of a school of fish... swimming around like inquiry ideas - fleeting and moving shapes..
Fish need to be netted - the net is not big enough to capture all the fish in the sea - but only collects the ones that fit into your net. This is like the way you identify and capture topics. After you have put the netted fish into your boat, you still need to ask some questions to further identify what type of fish you have caught.
Then a decision needs to be made on which fish (singular and plural) are the ones to concentrate on - to put into the container - to collect - in order to take to the kitchen and offer others as a meal of fish.
This is the the fish (singular or plural) that is served on a platter. First it is prepared through cooking - thinking through and theorising the ideas (fish) with expertise (cooking books telling you about good fish to eat) in order to understand the experience more profoundly. You need to know about the ideas (fish) but also how to catch and serve them...
At the end of the meal - others have eaten the fish - thought it was delicious - thought your fishing was really good - go away digesting your fish - and you now have the reputation as a superb fisherperson.