ЕТ
require(stringi)
str_vector <- c("asd(k) mama papa", "asd(5) mama papa", "^&$*(k) mama papa")
str_bad_vector <- paste0(c("asd(k)", "asd(5)", "^&$*(k)"), " ")
stri_replace_all_fixed(str_vector, pattern = str_bad_vector, replacement = "", vectorize_all = FALSE)