Perhaps you should try some spelling variations:
thanh cac » hanh cac, thanh bac, thanh ca
thu sach » tu sach, thuat sach, thuoc sach
sach nay » sach hay, sach vay, sach nang
cua viet » ca viet, hoa viet, cua vat
quan cua » ban cua, gian cua, quan ha
hieu ve » hieu va, hieu van
cac cua » cach cua, cac qua, ca cua
ve cam » ve cham, ve cac, va cam
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa

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 nay ((quan cua) OR (quan luan)) hoi. hieu ve cam ((luc va) or (tuc va)) thanh cac cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach nay ((quan cua) OR (quan luan)) hoi. hieu ve cam ((luc va) OR (tuc va)) thanh cac cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach nay ((quan cua) OR (quan luan)) hoi. hieu ve cam ((luc va) or (tuc va)) thanh cac cua viet".
• Adding a wildcard symbol may retrieve word variants: thu sach nay ((quan cua) OR (quan luan)) hoi. hieu ve cam ((luc va) or (tuc va)) thanh cac cua viet*.