3 Min Read SYDNEY, July 22 (Reuters) - The Australian and New Zealand dollars were trying to sustain a rally on Thursday as global sentiment improved a little, though the mounting economic impact of lockdowns in Australia meant risks remained to the downside. The Aussie bounced to $0.7350, having hit an eight-month trough of $0.7290 overnight. It needs to get above resistance at $0.7410 to break the current downtrend, which has now been running for five weeks. The kiwi dollar was hanging on at $0.6950, after also touching an eight-month low at $0.6882. Support lies at $0.6920 with resistance around $0.6980 and $0.7050. A rebound in world stock markets helped lessen the pressure on risk currencies, and the Aussie got some help from data showing Australia boasted a record goods surplus in June.