doc: minor typo fixes.

Author: agentzh

doc/HttpLuaModule.wiki

@@ -3791,9 +3791,9 @@ or a Lua table holding the query arguments' key-value pairs, as in
     ngx.req.set_uri_args({ a = 3, b = "hello world" })
 </geshi>
 
-In the former case, i.e., when the whole query-strng is provided directly,
+In the former case, i.e., when the whole query-string is provided directly,
 the input Lua string should already be well-formed with the URI encoding.
-For security considerations, his method will autoamticaly escape any control and
+For security considerations, his method will automatically escape any control and
 whitespace characters (ASCII code 0x00 ~ 0x32 and 0x7F) in the Lua string.
 
 In the latter case, this method will escape argument keys and values according to the URI escaping rule.