Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
nhung cong » dung cong, thong cong, hang cong
hoc thien » hoc hien, hoc thieu, hoc thiet
trinh van » trinh han, trinh quan, trinh toan
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap
tinh va » trinh vat, tinh gia, sinh vat

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 hach - nhanh ((((tinh va) or (tich va))) or (trinh van)) nhung cong tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - nhanh ((((tinh va) OR (tich va))) OR (trinh van)) nhung cong tap toan cao.
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - nhanh ((((tinh va) or (tich va))) or (trinh van)) nhung cong tap toan cao*.