Perhaps you should try some spelling variations:
viet cuu » viet suu, viet cau, viet chu
van anh » van thanh, tuan anh, van minh
sach ky » sach y, sach ty, sach kem
lang xa » lang ha, dang xay, lang van
cuu tre » cua tre, cau tren, cau treo
sac ky » cac ky, sai ky
ve bac » ve bao, ve ban, he bac
ve cac » va cac, vien cac

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 ky) or (sac ky)) lang xa hoi. hieu ((ve bac) OR (ve cac)) vo van anh viet cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) lang xa hoi. hieu ((ve bac) OR (ve cac)) vo van anh viet cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) lang xa hoi. hieu ((ve bac) OR (ve cac)) vo van anh viet cuu tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) lang xa hoi. hieu ((ve bac) OR (ve cac)) vo van anh viet cuu tre*.