a = 'sea'
URI("https://music.yandex.ru/search?text=#{a}")
#=> #<URI::HTTPS https://music.yandex.ru/search?text=sea>uri = URI('https://music.yandex.ru/search')
params = { :text => 'пятница' }
uri.query = URI.encode_www_form(params)
res = Net::HTTP.get_response(uri)doc = Nokogiri::HTML('<body><span class="title">Название:</span> Rising Water - James Vincent McMorrow<span></span><body>')
name = doc.xpath('//span/following-sibling::text()[1]').text
p name # => " Rising Water - James Vincent McMorrow"