Perhaps you should try some spelling variations:
cham luc » cham soc, nhan luc, cham cuu
dang xay » dang van, van xay
cau tren » cu tren, dau tren, ca tren
lang xa » lang ha, lang van
sach ky » sach y, sach ty, sach kem
va cham » va chat, va tham
va tinh » may tinh
tinh di » tinh doi, trinh di, tinh da
sac ky » cac ky, sai ky
luc va » duc va, tuc va, loc va
di cau » da cau, diem cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((sach ky) or (sac ky)) ((lang xa) OR (dang xay)) hoi. lieu va cham luc va tinh di cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((sach ky) OR (sac ky)) ((lang xa) OR (dang xay)) hoi. lieu va cham luc va tinh di cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((sach ky) or (sac ky)) ((lang xa) OR (dang xay)) hoi. lieu va cham luc va tinh di cau tren".
• Adding a wildcard symbol may retrieve word variants: hoc ((sach ky) or (sac ky)) ((lang xa) OR (dang xay)) hoi. lieu va cham luc va tinh di cau tren*.