With mature fabrication technologies and tunable spin relaxation, IIIV semiconductor two-dimensional quantum structures serve as a preferred material system for developing spintronic devices. This paper reviews the progress in manipulating spin-orbit coupling and spin relaxation in two-dimensional electron gas and two-dimensional hole gas systems via structural design, electric fields, and strain. By combining time-resolved magneto-optical spectroscopy with magnetotransport measurements, we analyze the synergistic modulation of Rashba and Dresselhaus effects to optimize the spin lifetime and highlight the distinct physical pathways for constructing long-lived SU(2) spin states in zinc-blende GaAs and wurtzite GaN heterostructures. For zinc-blende GaAs quantum wells, we discuss the realization of the persistent spin helix state by balancing the Rashba and Dresselhaus effects through structural design and electric field control. In contrast, for wurtzite GaN systems, we reveal that the Rashba and Dresselhaus effects inherently share the same symmetry form, allowing for the direct cancellation of effective magnetic fields to achieve a robust SU(2) electronic state. Ultimately, this comprehensive physical picture provides a scientific basis for material selection and architecture design in future high-performance spintronic devices.