Querying records with multiple filters

I want to query records using multiple filters like

sub_category_id=1 AND unit_offerprice > 1350

I am using dreamfactory version 2.1.0 as client for android
as advised in forum, I have used the following string as the filter

(sub_category_id%3D1) AND (unit_offerprice%3E1350)

and getting the following exception.

java.lang.IllegalArgumentException: Illegal character in query at index 94:
http://dreamfactory-xxx.xxx.com/api/v2/db/_table/product?filter=(sub_category_id%3D1) AND (unit_offerprice%3E1350)

Please suggest a right way to use multiple filters as the documentation is not helping me.

Preface: I don’t know anything about Java.

This is not a DreamFactory error, so a best guess is that the spaces in your URL need to be encoded: