"however elusive" is a correct phrase and can be used in written English.
It is usually used to introduce a contrasting idea or to express the difficulty of achieving something. For example: The truth may be hidden deep in the shadows, however elusive it may be.
The exactingly considered, quite beautiful arrangements of walls and works in the show sparkle with wit, however elusive the content of the jokes may be.
However elusive he may prove in Afghanistan, the terrorist suspected of orchestrating the attacks on the World Trade Center and the Pentagon is showing up around the United States with increasing frequency and on a variety of products, as an object of scorn and derision.
Nevertheless, just as the youngest of children have a keen sensitivity for what is "fair" (especially with regard to themselves), so it would seem that a passion for justice, however elusive a definition remains, is part of the makeup of any morally sentient being.
If faith truly is committed to the quest for truth, however elusive that truth may be, should it not point out the corrosive effect of the words we use to bend the truth?
In fact, it has allowed Hamas to claim victory (however elusive) and further embolden and increase its popularity as it was recognized, by virtue of being the counter-party to the negotiation of the ceasefire, as a separate entity to be reckoned with at the expense of both Israel and the Palestinian Authority.
From huge numbers of microscopic trajectories, understanding underlying processes are, however, elusive.
The impact of neuroinflammation on axonal degeneration in the peripheral nervous system is, however, still elusive.
How exactly the endothelium functions in this process, however, is still elusive and under investigation.
The mechanisms by which A20 regulates apoptotic signalling, however, are still elusive.
Economic recovery, however, proved elusive.
Edison the man, however, remains elusive.
