Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cau thuc » cau truc, cuu thuc, can thuc
vat hanh » vat thanh, van hanh, va hanh
lang xa » lang ha, dang xay, lang van
y lang » o lang, _ lang, tay lang
vi cua » vai cua, di cua
cua te » cua tu

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 lang xa hoi. ((hieu van) or (hieu qua)) cau thuc vat hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y lang xa hoi. ((hieu van) OR (hieu qua)) cau thuc vat hanh vi cua te.
• Adding a wildcard symbol may retrieve word variants: thu sach y lang xa hoi. ((hieu van) or (hieu qua)) cau thuc vat hanh vi cua te*.