Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
thien van » thi van
cau tren » cu tren, dau tren, ca tren
thanh vi » hanh vi, thanh va, thanh ve
tham hoc » thai hoc, tham hoa, than hoc
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach ky) or (sach y)) lang xa hoi. ((hieu ve) or (thien van)) tham hoc dan thanh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) lang xa hoi. ((hieu ve) OR (thien van)) tham hoc dan thanh vi cau tren.
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) or (sach y)) lang xa hoi. ((hieu ve) or (thien van)) tham hoc dan thanh vi cau tren*.