The Emerald Forest (1985) on Netflix

The American engineer Bill Markham moves with his wife Jean Markham and children to Amazonas to work in the construction of a dam. When he brings his son Tommy to the site forest, the boy is abducted by the tribe of the Invisible People and brought to rain forest. Bill spends ten years seeking out Tommy in the forest. When he finally meets Tommy, he is an Indian and does not want to leave his tribe and return to the civilization. But when Tommy's mate Kachiri and the women of his tribe are kidnapped by a gang of white slaves to work in a brothel in the forest, Tommy searches Bill in the big city to help his tribe to rescue the female Indians.