The phrase "are difficult to untangle" is correct and usable in written English.
It can be used when describing situations, problems, or concepts that are complex and hard to resolve or understand.
Example: "The issues surrounding climate change are difficult to untangle, as they involve numerous factors including politics, economics, and social behavior."
Alternatives: "are hard to decipher" or "are challenging to unravel."
Although the causal relationships are difficult to untangle, there are solid grounds for believing that the rise in monopoly power has played a role in exacerbating income inequality, weakening workers' bargaining power, and slowing the rate of innovation.
The force of these has confused modern commentators for a combination of reasons which, historically, are difficult to untangle.
Nevertheless, the scholars who do engage with the theory have identified substantial flaws, many of which are difficult to untangle without a substantial loss of meaning (Dovey 1990).
For example, a psychofunctional theory might be able to distinguish phenomena such as depression from sadness or listlessness even though the distinctive causes and effects of these syndromes are difficult to untangle solely by consulting intuitions or appealing to common sense.
In fact, studies consistently show that they commit significantly less crime than native-born Americans, and although the data are difficult to untangle, this appears to be true of both authorized and unauthorized immigrants.
It's difficult to untangle how cultural and economic pressures or biological hard-wiring influence parenting.
These observations have revealed a complex palimpsest of both massive irrigation systems and small scale karez/qanat systems that can be difficult to untangle.
That is because the company has such enormous and complex pension obligations and corporate overhead that it would be difficult to untangle them and sell properties individually.
It's difficult to untangle all the ways in which we subsidize each other's travels, whether by car or transit.
Further confusing much of the research into coffee is the fact that many coffee drinkers are also smokers, and it has been difficult to untangle the relative health effects of coffee and cigarettes.
Robert Provine, a psychologist at the University of Maryland and author of Laughter: A Scientific Investigation, said it is difficult to untangle whether the physiological effects are caused by the act of laughing or something else.
