Enlarge the term weight difference (#3435)

### What problem does this PR solve?


### Type of change

- [x] Performance Improvement

rag/nlp/query.py

@@ -66,7 +66,7 @@ class FulltextQueryer:
 
     def question(self, txt, tbl="qa", min_match:float=0.6):
         txt = re.sub(
-            r"[ :\r\n\t,，。？?/`!！&\^%%()^]+",
+            r"[ :\r\n\t,，。？?/`!！&\^%%()^\[\]]+",
             " ",
             rag_tokenizer.tradi2simp(rag_tokenizer.strQ2B(txt.lower())),
         ).strip()

rag/nlp/term_weight.py

@@ -228,6 +228,7 @@ class Dealer:
             idf2 = np.array([idf(df(t), 1000000000) for t in tks])
             wts = (0.3 * idf1 + 0.7 * idf2) * \
                 np.array([ner(t) * postag(t) for t in tks])
+            wts = [math.exp(s) for s in wts]
             tw = list(zip(tks, wts))
         else:
             for tk in tks:
@@ -236,6 +237,7 @@ class Dealer:
                 idf2 = np.array([idf(df(t), 1000000000) for t in tt])
                 wts = (0.3 * idf1 + 0.7 * idf2) * \
                     np.array([ner(t) * postag(t) for t in tt])
+                wts = [math.exp(s) for s in wts]
                 tw.extend(zip(tt, wts))
 
         S = np.sum([s for _, s in tw])