The phrase "make it difficult to understand" is correct and usable in written English.
You can use this phrase to describe a situation in which something is difficult to understand. For example, "The author's complex writing style makes it difficult to understand his message."
Its ambiguous epidemiology and the lack of tools for its specific detection make it difficult to understand and interpret the prevalence of this Anaplasma species.
Nevertheless, an evolutionary interpretation might make it difficult to understand how the commonly gradual process of forgetting was selected for.
That there is nothing heroic about him does not, contrary to much received opinion, make it difficult to understand his heroic music.
But he's being cunning about it; six major plans in one area, at one time, make it difficult to understand the extent of what is going on, and nearly impossible for residents to have their voices heard.
"As this industry has grown, lots of practices have grown up with it that make it difficult to understand.
Nevertheless, complicated rock properties such as low permeability, wettability, and other factors controlling flow mechanisms make it difficult to understand the flow characteristics and to generalize expected recovery.
The film received mixed reviews in China, where viewers complained that the film's "poor subtitle translation not only spoiled the fun of watching it, but also made it difficult to understand its humor".
RA is a complex chronic inflammatory disease dependent on multiple interacting environmental and genetic factors, making it difficult to understand its pathogenesis and thereby to find effective therapies.
However, Sall2 normal function, regulation and immediate target genes are not well known, making it difficult to understand its role in various diseases.
According to Hoffman, the wording of the CFAA makes it difficult to understand what is illegal.
The magnetic repulsion between two dipoles aligned side by side with their moments in the same direction makes it difficult to understand the phenomenon of ferromagnetism.
