Perhaps you should try some spelling variations:
soc thiet » hoc thiet, so thiet, toc thieu
van hanh » van thanh, ban hanh, van ban
cham vuc » cham soc, pham duc, cham cuu
thu sach » tu sach, thuat sach, thuoc sach
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
van anh » van thanh, tuan anh, van minh
hoi soc » hoi hoc, hoi suc, hoi so
va cham » va chat, va tham

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty ((nang xa) or (nang cao)) hoi. lieu va cham vuc ((van hanh) or (van anh)) hoi soc thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty ((nang xa) OR (nang cao)) hoi. lieu va cham vuc ((van hanh) OR (van anh)) hoi soc thiet.
• Adding a wildcard symbol may retrieve word variants: thu sach ty ((nang xa) or (nang cao)) hoi. lieu va cham vuc ((van hanh) or (van anh)) hoi soc thiet*.