Complex sentence: General Dyer tried to win over the Sikhs as best as he could, he asked the manager of the Golden Temple and Sunder Singh Majithia to use their influence with the Sikhs in favour of the government.
Split into simpler sentences: General Dyer tried to win over the Sikhs as best as he could. He asked the manager of the Golden Temple and Sunder Singh Majithia to use their influence over the Sikhs, in favour of the government.