Perhaps you should try some spelling variations:
sach kem » hanh kem
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
hieu te » hieu ve, hien te, hieu he
va hanh » van hanh, va thanh, va danh
sac ky » cac ky, sai ky
te ban » te bao
ban bo » can bo, ban do, ban co
vi cau » va cau, ve cau, di cau
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach kem) or (sac ky)) nang xa hoi. hieu te ban bo va hanh vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach kem) OR (sac ky)) nang xa hoi. hieu te ban bo va hanh vi cau tren.
• Adding a wildcard symbol may retrieve word variants: su ((sach kem) or (sac ky)) nang xa hoi. hieu te ban bo va hanh vi cau tren*.