Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hieu van » hieu va, thien van, lieu va
lang van » dang van, tang van, hoang van
cua viet » ca viet, hoa viet, cua vat
hoc sach » hoc sinh, hoc cac, hoc anh
lang xa » lang ha, dang xay
van cam » van nam, van lam, van cau
va hang » van hang, va nang, va lang
xuc va » duc va, tuc va, luc va
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sach) or (hoc sach)) y ((lang xa) or (lang van)) hoi. hieu van cam xuc va hang va cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) y ((lang xa) OR (lang van)) hoi. hieu van cam xuc va hang va cua viet.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) y ((lang xa) or (lang van)) hoi. hieu van cam xuc va hang va cua viet*.