why i can't convert chinese pdf successfully, all i got is garbled.

### Question

I got a chinese pdf, i want to convert to txt file ,but i got garbled. I already set lang=['en','ch_sim'] in EasyOcrOptions.

MY code is
```
from docling.document_converter import DocumentConverter
from docling.datamodel.base_models import InputFormat
from docling.datamodel.pipeline_options import PdfPipelineOptions, EasyOcrOptions
from docling.document_converter import PdfFormatOption, DocumentConverter

ocr_options = EasyOcrOptions(lang=['en','ch_sim'])

pipeline_options = PdfPipelineOptions()
pipeline_options.do_ocr = True
pipeline_options.do_table_structure = True
pipeline_options.table_structure_options.do_cell_matching = True
pipeline_options.ocr_options = ocr_options

converter = DocumentConverter(
format_options={
InputFormat.PDF: PdfFormatOption(pipeline_options=pipeline_options)
}
)

source = "C:/Users/53559/PycharmProjects/pythonProject/动手学深度学习.pdf" # document per local path or URL
# source = "https://arxiv.org/pdf/2408.09869"
result = converter.convert(source)
markdown_content = result.document.export_to_markdown()
print(markdown_content)
with open("C:/Users/53559/PycharmProjects/pythonProject/output4.txt", "w", encoding="utf-8") as file:
file.write(markdown_content)
```
docling 2.15.1
docling-core 2.14.0
docling-ibm-models 3.1.2
docling-parse 3.0.0