Sometimes Turnitin will highlight passages of text that do not necessarily need to be changed. Here are some examples of those.
If you have quoted a text in the correct manner - with quotation marks around the quoted material and a reference to where it came from - then you don't need to change these quotes. However, if there are too many quotes, you may want to turn some of them into paraphrases.
Lists of items or technical terms
When summarising information, sometimes you'll cluster items - ranging from book and film titles (like in the examples above) to symptoms of a disease to leading theorists in your field - closely together. It is likely that others have clustered items together in similar fashions. Sometimes you cannot change these details because the information is quite specific, and you can disregard highlights on these occasions. If it occurs often, however, you may need to revise slightly.
Sometimes items in a reference list will be highlighted. Sometimes in-text references will be too. Because you have to use a specific referencing style, and because other writers use the same style, it is inevitable that you will structure references in the same way. This cannot be helped, and you should not change the way you have referenced the source.