A method of using a set of subterranean manifold string (49, 70, 76) members for selectively controlling separate simultaneously flowing fluid mixture streams of varying velocities within one or more subterranean wells extending from a single main bore and wellhead, comprising the steps of: providing, at the upper end of said one or more subterranean wells, a subterranean disposed manifold string (49, 70, 76) member with a plurality of member conduit strings (2, 2A, 2B, 2C, 39, 50, 51, 71, 78); providing at least one manifold crossover member with at least one radial passageway member in fluid communication with at least one passageway (24, 24A, 24B, 25, 26, 53, 54, 55) member into communication with at least one conduit string member extending axially downward from said at least one manifold crossover member to at least one proximal region of said one or more subterranean wells; and selectively controlling said separate simultaneously flowing fluid streams of varying velocities between said wellhead and said at least one proximal region using one or more flow controlling members engaged between said member conduit strings or placeable through innermost passageway members or innermost passageway member connectors of said at least one manifold crossover member and engagable to at least one receptacle member placed between member conduit strings or within said at least one manifold crossover member, thereby urging substantially hydrocarbon or substantially water fluid mixtures of liquids, gases, solids, or combinations thereof, to or from said at least one proximal region; characterised by rotating, inverting, or reversing the orientation of said at least one manifold crossover member of said subterranean disposed manifold string and engaging said subterranean disposed manifold string with said wellhead to selectively control said simultaneously flowing fluid mixture streams of varying velocities between said wellhead and said at least one proximal region of said one or more subterranean wells. providing, at the upper end of said one or more subterranean wells, a subterranean disposed manifold string (49, 70, 76) member with a plurality of member conduit strings (2, 2A, 2B, 2C, 39, 50, 51, 71, 78); providing at least one manifold crossover member with at least one radial passageway member in fluid communication with at least one passageway (24, 24A, 24B, 25, 26, 53, 54, 55) member into communication with at least one conduit string member extending axially downward from said at least one manifold crossover member to at least one proximal region of said one or more subterranean wells; and selectively controlling said separate simultaneously flowing fluid streams of varying velocities between said wellhead and said at least one proximal region using one or more flow controlling members engaged between said member conduit strings or placeable through innermost passageway members or innermost passageway member connectors of said at least one manifold crossover member and engagable to at least one receptacle member placed between member conduit strings or within said at least one manifold crossover member, thereby urging substantially hydrocarbon or substantially water fluid mixtures of liquids, gases, solids, or combinations thereof, to or from said at least one proximal region; characterised by rotating, inverting, or reversing the orientation of said at least one manifold crossover member of said subterranean disposed manifold string and engaging said subterranean disposed manifold string with said wellhead to selectively control said simultaneously flowing fluid mixture streams of varying velocities between said wellhead and said at least one proximal region of said one or more subterranean wells.