"assiduous efforts" is a correct and usable phrase in written English.
It is used to describe when someone puts a great amount of effort and dedication into something. For example, "John has made assiduous efforts to improve his research skills this semester."
The assiduous efforts by Mr. Kerry and Mr. Biden to accommodate Republican concerns proved critical.
If assiduous efforts were made to bring emissions down, that date could be pushed back to 2069, the analysis found.
Some foreign fisheries are improving — Russia and Namibia, for example, have made assiduous efforts toward sustainable harvesting.
The texts illuminate Steele's assiduous efforts on Deripaska's behalf, in the months before the former MI6 officer began compiling the dossier, and also, the pair's connections to Waldman.
However, despite assiduous efforts to find strategies that help cardiovascular patients to adopt and maintain such behaviors, many studies of interventions designed to improve physical activity and adherence to medication have shown disappointing results.
It helped that early on in his term as Egypt's first-ever freely elected President Mr Morsi's poll ratings soared to almost 80%.Mr Morsi made assiduous efforts to keep the army and police sweet.
An assiduous effort was made to recover the prohibited books and to discover books and manuscripts that scholars had concealed in secret places.
This time he mounts an even more assiduous effort to woo women, and his true talent is an ability to write trick-filled, highly readable stories that flatter his readers.
They appear to be successful examples of "al Qaeda's assiduous effort to cultivate and train professional insurgents and urban warfare specialists via the Internet," wrote Scheuer, the former CIA analyst.
The decline was primarily the result of the slowing pace of the war; more fighting by Afghan forces, who use less lethal weapons; and an assiduous effort by the Western-led forces to reduce the impact on civilians, the report indicated.
I recommend you counter that inclination towards self-involvement with a deliberate and assiduous effort to consider others.
