Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
sach tay » xach tay, sach nay, sach tai
tinh hai » tinh thai, tinh chat, trinh han
sach hay » sach han, sach ha, sach nay
hieu van » hieu va, thien van, lieu va
hai cua » thai cua, dai cua, hoi cua
tang xa » trang xa, tang ma, lang xa
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach tay) or (sach hay)) tang xa hoi. hieu van nam ((xuc va) or (luc va)) tinh hai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach tay) OR (sach hay)) tang xa hoi. hieu van nam ((xuc va) OR (luc va)) tinh hai cua viet.
• Adding a wildcard symbol may retrieve word variants: te ((sach tay) or (sach hay)) tang xa hoi. hieu van nam ((xuc va) or (luc va)) tinh hai cua viet*.