Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
lang van » dang van, tang van, hoang van
tu sach » su sach, te sach, tu cach
van hoc » van hoa
hieu va » lieu va, hieu qua
cua van » cua ban, cua dan, cua can
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
va nam » van nam, ha nam, va nay
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) OR (thu sach)) y lang van hoc. hieu va nam ((cua van) or (cua vat)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) y lang van hoc. hieu va nam ((cua van) OR (cua vat)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) y lang van hoc. hieu va nam ((cua van) or (cua vat)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (thu sach)) y lang van hoc. hieu va nam ((cua van) or (cua vat)) hanh vi cua tre*.