[DOCS] Fixed typos and corrected grammar

docs/reference/api-conventions.asciidoc

@@ -20,14 +20,14 @@ API, unless otherwise specified.
 [[multi-index]]
 == Multiple Indices
 
-Most APIs that refer to an `index` paramter support execution across multiple indices,
+Most APIs that refer to an `index` parameter support execution across multiple indices,
 using simple `test1,test2,test3` notation (or `_all` for all indices). It also
 support wildcards, for example: `test*`, and the ability to "add" (`+`)
 and "remove" (`-`), for example: `+test*,-test3`.
 
 All multi indices API support the `ignore_indices` option. Setting it to
 `missing` will cause indices that do not exists to be ignored from the
-execution. By default, when its not set, the request will fail.
+execution. By default, when it's not set, the request will fail.
 
 NOTE: Single index APIs such as the <<docs>> and the
 <<indices-aliases,single-index `alias` APIs>> do not support multiple indices.

docs/reference/search/request/filter.asciidoc

@@ -10,7 +10,7 @@ Note, this is different compared to creating a `filtered` query with the
 filter, since this will cause the facets to only process the filtered
 results.
 
-For example, lets create two tweets, with two different tags:
+For example, let's create two tweets, with two different tags:
 
 [source,js]
 --------------------------------------------------
@@ -50,7 +50,7 @@ curl -XPOST 'localhost:9200/twitter/_search?pretty=true' -d '
 --------------------------------------------------
 
 We get two hits, and the relevant facets with a count of 1 for both
-`green` and `blue`. Now, lets say the `green` facet is chosen, we can
+`green` and `blue`. Now, let's say the `green` facet is chosen, we can
 simply add a filter for it:
 
 [source,js]
@@ -74,5 +74,5 @@ curl -XPOST 'localhost:9200/twitter/_search?pretty=true' -d '
 
 And now, we get only 1 hit back, but the facets remain the same.
 
-Note, if additional filters is required on specific facets, they can be
+Note, if additional filters are required on specific facets, they can be
 added as a `facet_filter` to the relevant facets.

docs/reference/search/request/script-fields.asciidoc

@@ -46,15 +46,15 @@ type). Here is an example:
     }
 --------------------------------------------------
 
-Note the `_source` keyword here to navigate the json like model.
+Note the `_source` keyword here to navigate the json-like model.
 
-Its important to understand the difference between
+It's important to understand the difference between
 `doc['my_field'].value` and `_source.my_field`. The first, using the doc
 keyword, will cause the terms for that field to be loaded to memory
 (cached), which will result in faster execution, but more memory
 consumption. Also, the `doc[...]` notation only allows for simple valued
-fields (can't return a json object from it) and make sense only on non
-analyzed or single term based fields.
+fields (can't return a json object from it) and make sense only on
+non-analyzed or single term based fields.
 
 The `_source` on the other hand causes the source to be loaded, parsed,
 and then only the relevant part of the json is returned.