LibreOffice Math: Symbols Missing?

Missing3.PNGHello, I am new to LibreOffice Math. When I first opened it up, some important symbols like ‘equals’ appeared as a floppy disk; I fixed this by downloading the OpenSymbols TrueType Font. But now, there are still many symbols missing, specifically:

-one in Unary/Binary Operators,

-a few in Relations,

a few in Attributes,

-most of them in Brackets, and

-one in Others

I have attached an image of each of the problems.

Is there another font type I have to download, or what can I do to recover these symbols?

Thanks.

Now you have enough karma to attach an image.

Thanks; I attached one.