• Built potential SEM upgrading plans by conducting research on L'Oréal's brand positioning and market demand and creating scenarios for their usage to maximize the database's coverage; Offered insights to integrate their strategies into TikTok and WeChat advertising inputs.• Pioneered the integration of disparate data sets into a cohesive database, employing Python programming skills to manage data and resolve data missing problems, and ensuring high data integrity.• Leveraged the database’s long-tail effect to identify efficient keyword combinations, enhancing the brand’s average CTR by 5.3%; Utilized MySQL and Tableau to process backend monitoring data, analyze and adjust advertising strategies, resulting in a 2.6% increase in ROI; Managed and allocated advertising budgets, making timely adjustments based on data performance, which reduced the average CPC by 12%.• Mapped the relationship between user persona keywords and product advertising keywords by employing regression analysis, devising and validating a strategic hypothesis on audience discovery mechanisms; Optimized search pathways, leading to a 30% reduction in average user search chains and a 19% increase in effective user conversion rates.