Under which circumstances is it proper English to say, e.g.
I find this book [adjective].
A common example seems to be
I find this book difficult to read.
From my native language I am inclined to generalize the above construction, and use "to find" in the sense of "to regard"/"to consider"
I find this book difficult, entertaining, and too sophisticated.
It is not evident to me whether the above sentence represents proper English. For example, the phrase "I find this entertaining" returns too many hits as too debunk it as wrong immediately.
Can somebody clarify the usage of "to find" with adjectives?