is there a way to search specific word in a twitter timeline over a period of time?

I am doing some twitter analysis in R, right now im getting the tweets from an account, but i want to search for 1 or more specific words inside those tweets and then do a plot that shows how much has the word been repeated over a period of time, for example 1 week.

this is my script:

#instalar librerias
library(wordcloud)
library(SnowballC)
library(rtweet)
library(tm)
library(RColorBrewer)
library(tidytext)
library(dplyr)
library(wordcloud2)
library(stringr)
library(qdapRegex)

# Identificacion y obtencion de tokens
appname <- "AnalisisTwitSent"
consumer_key     <- "CvgpjfxMIyUmg21HFPSKoFKr4"
consumer_secret  <- "5VO0fWH6QK5jyYWx4PtABHyhvvZ5JyVjDNjQ2F36mDjYibu5g7"
access_token <- "2820319925-CTKOd9yiA8MmJlak1iXUDCbg2MKkKDlffjr9LyV"
access_secret <- "ZiZBJIjxqY9lNLemYdGxMD6BYM6eY43NyLGhRS4NRKu5S"

twitter_token <- create_token(app = appname, 
                           consumer_key = consumer_key, 
                           consumer_secret = consumer_secret,
                           access_token = access_token, 
                           access_secret = access_secret,
                           set_renv = TRUE)

ver_palabras_comunes_nube <- function(busqueda, cantidad) {

  #Obtener tweets
  #tweets <- get_timeline(usuario, n = cantidad, 
                     #parse = TRUE, check = TRUE,
                     #include_rts = TRUE)
  tweets <- search_tweets(busqueda, cantidad, include_rts = FALSE)

  text <- str_c(tweets$text, collapse = "")

  # continue cleaning the text
  text <- 
    text %>%
    str_remove("\\n") %>%                   # remove linebreaks
    rm_twitter_url() %>%                    # Remove URLS
    rm_url() %>%
    str_remove_all("#\\S+") %>%             # Remove any hashtags
    str_remove_all("@\\S+") %>%             # Remove any @ mentions
    removeWords(stopwords("spanish")) %>%   # Remove common words (a, the, it etc.)
    removeNumbers() %>%
    stripWhitespace() %>%
    removeWords(c("amp"))                   # Final cleanup of other small changes
    gsub("\\p{So}|\\p{Cn}", "", text, perl = TRUE)


  rm_emoticon(text, replacement = "")

  # Convert the data into a summary table
  textCorpus <- 
    Corpus(VectorSource(text)) %>%
    TermDocumentMatrix() %>%
    as.matrix()

  textCorpus <- sort(rowSums(textCorpus), decreasing=TRUE)
  textCorpus <- data.frame(word = names(textCorpus), freq=textCorpus, row.names = NULL)

  wordcloud <- wordcloud2(data = textCorpus, minRotation = 0, maxRotation = 0)
  wordcloud
}