Perhaps you should try some spelling variations:
thuoc sach » nuoc sach, thuat sach, thuoc sinh
hoc sach » hoc sinh, hoc cac, hoc anh
tay tang » tay lang, tay trung, tay quang
hieu van » hieu va, thien van, lieu va
ban hanh » ban hang
tang xa » trang xa, tang ma, lang xa
van coc » van hoc, van loc, van co
coc cua » hoc cua, co cua, con cua
vai cua » hai cua, lai cua, bai cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thuoc sach) OR (hoc sach)) tay tang xa hoi. hieu van coc cua ban hanh ((vai cua) or (dai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (hoc sach)) tay tang xa hoi. hieu van coc cua ban hanh ((vai cua) OR (dai cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuoc sach) OR (hoc sach)) tay tang xa hoi. hieu van coc cua ban hanh ((vai cua) or (dai cua)) te".
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) OR (hoc sach)) tay tang xa hoi. hieu van coc cua ban hanh ((vai cua) or (dai cua)) te*.