Find the Word v4

#include<stdio.h>
#include<string.h>


void FindWord (char letters[30] , char string[30] , int wordsize);
char* CleanString (char string[30], int wordsize);

int main (void)
{
    FILE *fp;
    char letters[30];
    char words[30];
    char used[30]={0};
    char *string;
    int wordsize;
    int input_size;


    fp = fopen("dictionary.txt","r");/*contains a list of words in the following format : number_of_chars.word (i.e. 2.hi , 4.stop )*/
    if (fp == NULL) {printf("\nError : dictionary.txt , no such file or directory!");}

while(fp != NULL)
{
        rewind(fp);
        printf("Type the letters and press enter : ");
        gets(letters);/* saves the inputed data to a string*/
        fflush(stdin);

        input_size = strlen(letters);/* gets how many characters user entered*/


        while (1)
        {
            fscanf(fp,"%d",&wordsize);/* will read the number (i.e. for 2.hi will read 2) to determine the size of the word*/
            string = fgets(words, 30 , fp);


            if (string == NULL) /*if the file ends or we have an error, break*/
                                    break;
            if (input_size != wordsize) /*if the number of letters we inputed is different from the size of the word in question , skip it*/
                                    continue;


            CleanString (string, wordsize);/*This function removes the number_of_letters. from the string "string" .*/
            FindWord (letters, string, wordsize);/* this function checks if the letters inputed can make a word and if so , prints it*/

        }

}
    fclose(fp);

}

void FindWord (char letters[30] , char string[30] , int wordsize)
{
    int not_matched,not_matched_rev;
    bool wordfound = true;
    not_matched = not_matched_rev = 0;

            for ( int i = 0; i<wordsize; i++)
            {
                not_matched = 0;
                not_matched_rev= 0;

                for ( int j = 0; j<wordsize; j++)
                {
                    if (letters[i] != string[j])
                                        not_matched++;
                    if (letters[j] != string[i])
                                        not_matched_rev++;
                    if (not_matched == wordsize || not_matched_rev ==  wordsize)
                        {
                            i = wordsize + 1;
                            wordfound = false ;
                        }

                }
            }

            if(wordfound)
            {
                printf("\t->%s\n",string);
                fflush(stdout);
            }
}

char* CleanString (char string[30], int wordsize)
{
    for (int i = 0; i<=2; i++)
    {
        if (string[i] == '.')
        {
            for (int j = 0; j <= wordsize; j++)
                                     string[j] = string[(i+1)+j];
        }

    }
    string[wordsize] = '\0';

    return string;
}