Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sang mai » sang ma, sang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
dan vat » dang vat, van vat, dan va
la tren » loai tren, dua tren, dat tren
y sang » _ sang, duy sang
ve cac » va cac, vien cac
xuc va » duc va, tuc va, luc va
va dan » ca dan, va dao, va dau
vat la » vat ly, vat li, vat 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 y sang mai hoi. hieu ((va bai) or (ve cac)) xuc va dan vat la tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y sang mai hoi. hieu ((va bai) OR (ve cac)) xuc va dan vat la tren.
• Adding a wildcard symbol may retrieve word variants: thu sach y sang mai hoi. hieu ((va bai) or (ve cac)) xuc va dan vat la tren*.