Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuoc sinh
thuat sach » thuat lanh, thuat san
van tuan » van quan, van ban, anh tuan
nang ma » tang ma, sang ma, nang cao
tru van » truc van, tu van, tru va
cac tru » ca tru, cac tro, cac thu
ma hoi » mai hoi, xa hoi, ma hoa
y nang » ky nang, ly nang, v nang
vai va » mai va, dai va, lai va
hai va » hai van, thai va, hoi va

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 (thuat sach)) y nang ma hoi. lieu va cac tru van tuan ((vai va) OR (hai va)) trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (thuat sach)) y nang ma hoi. lieu va cac tru van tuan ((vai va) OR (hai va)) trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuoc sach) or (thuat sach)) y nang ma hoi. lieu va cac tru van tuan ((vai va) OR (hai va)) trien".
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) or (thuat sach)) y nang ma hoi. lieu va cac tru van tuan ((vai va) OR (hai va)) trien*.