function to check if word matches search word

I have the following which works but was wondering if there's a better way. Better meaning more efficient and or more compact.

The function checks a trie to see if the word is in the trie.

bool check(const char *word)
{        
    int nodeIdx = hash(word);     
    if (nodeIdx < 0)return false;       

    nodeWords * searchNode;    
    searchNode = nodeArray[nodeIdx];  //nodeArray is global    
    bool whileFlag = true, returnFlag = false;
    
    do
    {
        if (strcmp(word,searchNode->word) == 0 ) 
        {
            whileFlag = false;
            returnFlag = true;
        }
        else if (strcmp(word,searchNode->word) < 0 )
        {            
            if(searchNode->left == NULL)
            {
                whileFlag = false;
            }else{
                searchNode = searchNode->left;
            }
        }else{               
            if(searchNode->right == NULL)
            {                
                whileFlag = false;
            }else{
                searchNode = searchNode->right;
            }
        }
    }while (whileFlag);    

    free(searchNode);    
    return returnFlag;
}

for instance, we could rewrite the function this way:

bool check(const char *word)
{   
    int nodeIdx = hash(word);   
    if (nodeIdx < 0)return false;    

    nodeWords * searchNode; 
    searchNode = nodeArray[nodeIdx];    
    bool returnFlag = false;    

    do
    {
        if (strcmp(word,searchNode->word) == 0 )returnFlag = true;
        else if (strcmp(word,searchNode->word) < 0 && searchNode->left  != NULL) searchNode = searchNode->left;
        else if (strcmp(word,searchNode->word) > 0 && searchNode->right != NULL) searchNode = searchNode->right;
    }while (searchNode->left != NULL || searchNode->right != NULL || strcmp(word,searchNode->word) == 0);    
    
    return returnFlag;
}