address Chris' comments

client/tx/search.go

@@ -32,7 +32,7 @@ func SearchTxCmd(cdc *codec.Codec) *cobra.Command {
 		Long: strings.TrimSpace(`
 Search for transactions that match exactly the given tags. For example:
 
-$ gaiacli query txs --tags <tag1>:<value1>&<tag2>:<value2>
+$ gaiacli query txs --tags '<tag1>:<value1>&<tag2>:<value2>'
 `),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			tagsStr := viper.GetString(flagTags)
@@ -48,7 +48,10 @@ $ gaiacli query txs --tags <tag1>:<value1>&<tag2>:<value2>
 			for _, tag := range tags {
 				if !strings.Contains(tag, ":") {
 					return fmt.Errorf("%s should be of the format <key>:<value>", tagsStr)
+				} else if strings.Count(tag, ":") > 1 {
+					return fmt.Errorf("%s should only contain one <key>:<value> pair", tagsStr)
 				}
+
 				keyValue := strings.Split(tag, ":")
 				tag = fmt.Sprintf("%s='%s'", keyValue[0], keyValue[1])
 				tmTags = append(tmTags, tag)

docs/gaia/gaiacli.md

@@ -193,8 +193,18 @@ gaiacli tx broadcast --node=<node> signedSendTx.json
 
 You can use the transaction search command to query for transactions that match a specific set of `tags`, which are added on every transaction.
 
+Each tag is conformed by a key-value pair in the form of `<tag>:<value>`. Tags can also be combined to query for a more specific result using the `&` symbol.
+
+The command for querying transactions using a `tag` is the following:
+
+```bash
+gaiacli query txs --tags='<tag>:<value>'
+```
+
+And for using multiple `tags`:
+
 ```bash
-gaiacli query txs --tags=<tag1>:<value1>&<tag2>:<value2>
+gaiacli query txs --tags='<tag1>:<value1>&<tag2>:<value2>'
 ```
 
 ::: tip Note