Perhaps you should try some spelling variations:
cham luc » cham soc, nhan luc, cham cuu
van hanh » van thanh, ban hanh, van anh
dua tren » dung tren
sach ky » sac ky, sach y, sach kem
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua
va cham » va chat, va tham
luc van » luoc van, luu van, duc van
cuu tre » cua tre, cau tren, cau treo
kem » kiem

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 ty)) nang x ho. hieu va cham luc van hanh kem ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach ty)) nang x ho. hieu va cham luc van hanh kem ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) or (sach ty)) nang x ho. hieu va cham luc van hanh kem ((dua tren) or (cuu tre))*.