Perhaps you should try some spelling variations:
thien danh » thien anh, thien dang, thien thanh
quang dung » quang trung, ung dung, cuong dung
hoc thien » hoc hien, hoc thieu, hoc thiet
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
dung cong » dung trong
tac toan » tap toan, tam toan, hach toan
bai toan » bai tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien danh - hanh tinh quang dung cong ((tac toan) or (bai toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien danh - hanh tinh quang dung cong ((tac toan) OR (bai toan)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc thien danh - hanh tinh quang dung cong ((tac toan) or (bai toan)) cau*.