Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
viec cac » vien cac, viec cua, viec lam
vinh cua » sinh cua, tinh cua, dinh cua
van hanh » van thanh, ban hanh, van ban
van anh » van thanh, tuan anh, van minh
tu sach » thu sach, su sach, te sach
cac xuc » cam xuc, cac nuoc, chat xuc
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
cua tre » cua te, cuu tre, cua triet

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 (lang xa)) hoi. hieu viec cac xuc ((van anh) or (van hanh)) vinh cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu viec cac xuc ((van anh) OR (van hanh)) vinh cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (lang xa)) hoi. hieu viec cac xuc ((van anh) or (van hanh)) vinh cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu viec cac xuc ((van anh) or (van hanh)) vinh cua tre*.