Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
nang mai » nang ma, nang tai, lang mai
dua tren » dung tren
mai hoi » mai khoi, dai hoi, lai hoi
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
va cam » va cham, va cao, va cai
luc va » duc va, tuc va, loc va
vi dua » vi du, vi dum, vi lua

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 nang mai hoi. lieu ((va cam) OR (va cac)) luc va hanh vi dua tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang mai hoi. lieu ((va cam) OR (va cac)) luc va hanh vi dua tren".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang mai hoi. lieu ((va cam) OR (va cac)) luc va hanh vi dua tren*.