If you'd like a hint keep reading :
At the top of diptera and haemolacria it says the page is red or blue.
When you flip each word in the puzzle, you can see some become blue, some become red.
The goal is for each page to have all the words of their color showing.
You need to use both pages to learn the color of each word, since each page only has half of the answers.
Glad to see you're enjoying your time so far, good luck!