Exporting Transactions to SAP Business One 
Transactions recorded in sales and purchasing documents can be copied from one company to another in SAP Business One. The transactions are exported from the source company and then imported into target company.
Before exporting the transactions, ensure that the master record numbers in the G/L accounts and the business partners that are contained in the postings are identical in both companies. If a master record for a G/L account or business partner does not exist yet in the target system, the system creates this object automatically in accordance with the data in the posting.
You can also select accounting documents for export through the underlying original journal documents. For example, you can export all accounting documents that were created as the result of incoming (AP) invoices. You can also select several original journals at the same time.
If you regularly export transactions from the source company and import them into the target company, it is recommend to keep a record outside SAP Business One of the transactions that were copied during each operation.
If you run SAP Business One in a network at your company, make sure that no other users are logged on when you start exporting the transactions.
Procedure
Log on to the company in SAP Business One from which you want to export the data.
Choose
Administration 
Data Import/Export Data Export Export Transactions to SAP Business One 
.In the Export Transactions to SAP Business One window, choose the parameters for selecting the transactions to be exported. The checkbox on left of each parameter field must be checked for that range to be selected. If you specify multiple parameters, only the documents that meet all the parameters will be exported.
You can select accounting documents by the document number, the reference numbers Ref 1 and Ref 2 (from the Journal Entries, for example an Invoice number), the transaction code, and the project number. You can limit the export to documents with a specific total amount in the local, system, and/or foreign currency. To select documents that contain a certain text or string, type this text or string in the Details Contain field.
In addition, select accounting documents through certain original journals on the right side. Original Journal must be checked for any of the fields in the column on the right to be selected. Specify the value range for that parameter in the fields to the right.
You can specify both selection parameters and original journals for an export operation. In this case, the documents from the original journals that fulfill the parameters in the left half of the screen will be exported.
To export all the accounting documents, select Choose All. This selection becomes the default the next time this window is selected.
When you have selected all the necessary accounting documents, choose OK. The file manager displays. Indicate where you want to save the file, for example, on the hard drive or on a data medium. If you want to specify a custom file name, simply overwrite the default. The file must be saved in a .txt format.
Choose Save in the file manager. The progress of export is displayed in the status bar. A Stop button appears in the status bar during the export to enable termination of the procedure if required. The Message window displays as soon as the document export has been completed successfully.