"striving hard" is a correct and usable phrase in written English. You can use it to refer to someone who is making a determined effort to achieve something, such as: "She was striving hard to complete the project before the deadline.".
"He was striving hard for the team and it was unfortunate," said Woakes.
It harms a certain kind of public good that many Americans are striving hard to attain — the public good of a society where people feel safe, valued and at home in their social home.
Other ventures are striving hard to be transparent about their impact – for example, B4Box has calculated that for every pound spent on its services, between £2 and £8 are saved by society.
The Economic Community of West Africa States (Ecowas), the 16-nation regional grouping of which Liberia is a member, called Tubman's decision "unfortunate", saying, "it is intended to undermine the election and the democratic process that Liberians are striving hard to consolidate".
Myers spends her childhood striving harder than her mother and her sisters, and she disdains their lack of ambition.
If striving harder to get higher turns out not to be the rosy picture you'd painted, you have a great opportunity now to start reassessing your direction.
Mr Koons strives hard to create convincing illusions.
I love the desktop app, it’s always running on my Mac. Ludwig is the best English buddy, it answers my 100 queries per day and stays cool.
Cristina Valenza
Retail Lead Linguist @ Apple Inc.