Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
va hanh » va thanh, va danh, ban hanh
lo lang » o lang, so lang, hoa lang
vai cua » dai cua, hai cua, lai cua
le lang » le tang, le dang, le xang
hieu va » lieu va, hieu qua
cam luc » cam xuc, cau luc
va cam » va cham, va cac, va cao
cua tu » cua tuc, cua su, cua cu

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 ((lo lang) or (le lang)) xa hoi. hieu va cam luc ((va hanh) OR (van hanh)) vai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((lo lang) OR (le lang)) xa hoi. hieu va cam luc ((va hanh) OR (van hanh)) vai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((lo lang) or (le lang)) xa hoi. hieu va cam luc ((va hanh) OR (van hanh)) vai cua tu".
• Adding a wildcard symbol may retrieve word variants: thu sach ((lo lang) or (le lang)) xa hoi. hieu va cam luc ((va hanh) OR (van hanh)) vai cua tu*.