Those who witness no falsehood, and, if they pass by futility, they pass by it with honourable (avoidance);
Zura has several meanings, such as crookedness, forgery, fraud, falsity and such. The basic idea is that a believer does not put him or herself into situations where he or she will have to witness corruption, crime and deceit. The Muslim does not keep company with dishonest people, nor does the Muslim get involved in shady schemes.
Living in our world, it is impossible to isolate oneself completely from the foolishness and corruption that goes on all around us. As believers, we must try to keep as much of it away as possible, for Islam has no conception of accommodation or assimilation into godless cultures, despite what some modernists would like to believe. (See 18:28). A believer must spend the lion’s share of his or her waking hours among other believers, and he or she must spend the bulk of his or her time in a wholesome, God-oriented environment. When the believer does witness foolishness or immorality, such as people dancing shamelessly in public, lewd advertisements, shameless public displays of intimacy or drunkenness and such, he or she is to hold his or her head up high and pass by without giving such displays any credence or undue attention. Basically, a Muslim has to ignore it with dignity and get away from it as quickly as possible.
Emerick, Yahiya. The Meaning of the Holy Qur’an in Today’s English (p. 829). Unknown. Kindle Edition.