Here are some prefixes. I send you two lists: one with accents, and one without. In Spanish people tend to search without accents on desktop and with accents on mobile (because of the auto-dictionary) so feel free to choose.
("quien es *", "qué es *","dónde", "dónde esta *", "cuándo *", "por qué *", "cómo *", "mejor", "barato", "peor", "es", "qué", "cuando", "quién","cuál es","cuánto",)
("quien es *", "que es *","donde", "donde esta *", "cuando *", "por que", "como *", "mejor", "barato", "peor", "es *", "que", "cuando", "quien","cual es","cuanto",)
Please do let me know if I can be of further help :)
Best,
Juan