Perhaps you should try some spelling variations:
tinh viet » trinh viet, ninh viet, dinh viet
tinh vien » sinh vien, tinh dien, tinh hien
thu sach » tu sach, thuat sach, thuoc sach
hieu cua » hieu qua, dieu cua, bieu cua
cac truc » cau truc, cac tru, cac trung
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
truc va » thuc va, thuc vat, trung va

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 lang xa hoi. hieu cua cac truc va ((tinh vien) OR (tinh viet)) cac tro~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky lang xa hoi. hieu cua cac truc va ((tinh vien) OR (tinh viet)) cac tro".
• Adding a wildcard symbol may retrieve word variants: thu sach ky lang xa hoi. hieu cua cac truc va ((tinh vien) OR (tinh viet)) cac tro*.