Perhaps you should try some spelling variations:
cham duc » pham duc, cham soc, pham duy
hanh tai » thanh tai, hang tai, han tai
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
va cham » va chat, va tham
va hanh » van hanh, va thanh, va danh
tai va » thai va, mai va, tri va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((nang xa) or (nang ma)) hoi. lieu va cham duc va hanh tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang ma)) hoi. lieu va cham duc va hanh tai va thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (nang ma)) hoi. lieu va cham duc va hanh tai va thiet*.