You can take Guangzhou metro line 2(https://www.travelchinaguide.com/cityguides/guangdong/guangzhou/subway/line2.htm) from Haizhu plaza to Gongyuanqian, then transfer to Subway line 3 . Comtinue to transfer Guangfo Line at Xilang. You will get to Kuiqi Lu, Foshan. Then you can catch a taxi to Nanhai Yin Temple. You may be clear about this tramsfer through Guangzhou Subway Map(https://www.travelchinaguide.com/cityguides/guangdong/guangzhou/subway/metro-map.htm) .

Hi Hing,
Which Nanhai KwanYin Temple do you want to go? there are two nanhai kwanyin in nanhai.one is in nanguotaoyuan in guanyao town,nanhai,one is in xiqiao mountain in xiqiao town,nanhai.