1. new a Calc, modify name of sheet2 and make sure it contains space, e.g. "sheet 2"
2. save as link.ods
3. new a calc
4. insert a document hyperlink, select link.ods as document, then click the "target in document" button
5. select sheet1 as target, apply. Now a hyperlink to link.ods->sheet1 is created.
6. repeat steps 4&5 but this time select "sheet 2" as target.
7. save and reopen
8. select each hyperlink then click the hyperlink button on toolbar or click menu insert->hyperlink to call out the hyperlink dialog. 

minor issue: when check the hyperlink to "sheet 2" you will find space character is replaced by "%20". though it's formula of hyperlink address, I think it will be better if user's original input can be reserved.

9. click "target in document" to check the target

expect:"sheet 2" is highlighted in "target in document" dialog
actual:"Sheets" is highlighted.

the hyperlink to sheet1 which has no space in target name is correct.