Whether you apply Google Trends through the website or writing a program to call the API, as long as you use the service of Google Trends, you can only search for up to five keywords at a time. This is a restriction set by Google and cannot be changed. Then why can the Google Trends Enhanced search multiple keywords at once? The task Google Trends Enhanced does is to group all keywords, obtain each search interest, then merge the data, and export it into a Excel file.
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