Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thien van » thi van
thu sach » tu sach, thuat sach, thu hoach
van hanh » van thanh, ban hanh, van anh
dat van » dao van, dat va, dam van
cac dat » cac dan, cai dat, cac dai
van cac » van hac, van cau, van bac
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
vi cua » vai 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: ((thu sach) or (thuoc sach)) ky ((nang ma) or (sang ma)) hoi. thien van cac dat van hanh vi cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuoc sach)) ky ((nang ma) OR (sang ma)) hoi. thien van cac dat van hanh vi cua vat.
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thuoc sach)) ky ((nang ma) or (sang ma)) hoi. thien van cac dat van hanh vi cua vat*.