Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
van cham » van chat, van tham, van pham
han thai » han tai, ban thai, van thai
nang xa » nang x, lang xa, nang ma
va cham » va chat, va tham
thai va » thai van
y nang » ky nang, ly nang, v nang
xuc va » tuc va, luc va, xac va
thiet » thieu

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 xa hoi. hieu ((van cham) OR (va cham)) ((xuc va) or (duc va)) han thai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang xa hoi. hieu ((van cham) OR (va cham)) ((xuc va) OR (duc va)) han thai va thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang xa hoi. hieu ((van cham) OR (va cham)) ((xuc va) or (duc va)) han thai va thiet".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang xa hoi. hieu ((van cham) OR (va cham)) ((xuc va) or (duc va)) han thai va thiet*.