If we do hematology test we find blood cancer in this test?

Not necessarily. Blood cancers, also called leukemias, result in high numbers of white blood cells. Acute leukemia can often be found on a routine blood test. However, not all blood cancers can be found this way. A diagnosis of blood cancer usually requires a history and physical exam in addition to blood tests. That's why it's important you see your doctor! There's more to the story than just a test.
Maybe. There are many kinds of blood cancers, not just leukemia, and they may not always be evident on a complete blood count, or cbc. Sometimes we see abnormal cells in the blood, which comfirms a leukemia, but that is not always the case. Diagnosing blood cancers requires history, physical exam, multiple blood tests and possibly bone marrow or lymph node biopsy. It's a complicated process.

Related Questions

I m say my doctor I wana test. Blood cancer. ..... He recommends hematology profile test. Is gud to see all. Blood cancer?

Initial CBC. Blood cancer is a vast subject area with many complex examples. However, routine 'hematology profile' (various counts) is a good begining.