GREIF and DENIAL are major topics in A Monster Calls. As an example think of Conor's attempts to make things appear normal and his rage whenever changes are discussed.
To start you can - from the Library's Advanced Search screen - change the field that contains "Any Field" to Subject and then in the first search field add grief (This is saying that everything you are searching will be about grief) then in the second search field add child* (the * indicates to the database that you want to use both child and children. Other terms to try include bereavement, loss, parental death, and parental loss.
Search result example:
The YEW TREE is an important symbol within the book and can be looked at through a cultural lens. Consider this quote, "The yew tree is the most important of all the healing trees, it said. It lives for thousands of years. Its berries, its bark, its leaves, its sap, its pulp, its wood, they all thrum and burn and twist with life. It can cure almost any ailment man suffers from, mixed and treated by the right apothecary." (105)
Try using "yew tree" (in parenthesis to search that exact statement) in the first search field and then history in the second. If that doesn't yield good results, try changing the "Any Field" before history to Subject, and try again. You might also have success with other terms such as"English history" or "The Green Man"
Search results example: