Perhaps you should try some spelling variations:
cham loc » cham soc, chon loc, cham o
dua tren » dung tren
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
cua tre » cua te, cuu tre, cua triet
san ky » sang ky, dan ky, ban ky
loc va » hoc va, luc va
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((san ky) or (van ky)) lang xa hoi. hieu ve cham loc va dan vi ((dua tren) or (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((san ky) OR (van ky)) lang xa hoi. hieu ve cham loc va dan vi ((dua tren) OR (cua tre)).
• Adding a wildcard symbol may retrieve word variants: tu ((san ky) or (van ky)) lang xa hoi. hieu ve cham loc va dan vi ((dua tren) or (cua tre))*.