Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
van hanh » van thanh, ban hanh, van anh
tu sach » su sach, te sach, tu cach
vai cua » dai cua, hai cua, lai cua
duc van » duc va, duc tan, duc manh
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
lang ha » long ha
ky lang » ky nang, ky dang, ky tang
ha hoi » hoa hoi, ha noi, xa hoi
va cam » va cham, va cac, va cao
vi 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)) ky lang ha hoi. hieu va cam duc van hanh ((vi cua) or (vai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky lang ha hoi. hieu va cam duc van hanh ((vi cua) OR (vai cua)) tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky lang ha hoi. hieu va cam duc van hanh ((vi cua) or (vai cua)) tre*.